*1332This consolidated action is before the court on two motions for judgment on the agency record challenging various aspects of the U.S. Department of Commerce's ("Department" or "Commerce") final determination in the tenth administrative review of the antidumping duty ("ADD") order covering certain frozen warmwater shrimp from the Socialist Republic of Vietnam ("Vietnam"). See Pls. & Pl.-Intervenor's Rule 56.2 Mot. J. Agency R., June 5, 2017, ECF No. 38; Consol.-Pl.'s Rule 56.2 *1333Mot. J. Agency R., June 5, 2017, ECF No. 39; see also Certain Frozen Warmwater Shrimp From [Vietnam], 81 Fed. Reg. 62,717 (Dep't Commerce Sept. 12, 2016) (final results of [ADD] administrative review, 2014-2015) ("Final Results") and accompanying Certain Frozen Warmwater Shrimp from [Vietnam]: Issues and Decision Mem. for the Final Results, A-552-802, (Sept. 6, 2016), ECF No. 19-2 ("Final Decision Memo"); Certain Frozen Warmwater Shrimp From [Vietnam], 70 Fed. Reg. 5,152 (Dep't Commerce Feb. 1, 2005) (notice of amended final determination of sales at less than fair value and [ADD] order) ("ADD Order").
Plaintiffs Soc Trang Seafood Joint Stock Company a/k/a Stapimex et al., foreign producers and exporters of the subject merchandise, commenced this action pursuant to section 516A(a)(2)(B)(iii) and 516A(d) of the Tariff Act of 1930, as amended, 19 U.S.C. § 1516a(a)(2)(B)(iii) and 1516a(d) (2012).1 See Summons, Oct. 7, 2016, ECF No. 1; Compl., Oct. 28, 2016, ECF No. 8.2 Plaintiff-Intervenor, Ca Mau Seafood Joint Stock Company a/k/a Seaprimexco Vietnam, intervened as of right, see Order, Mar. 1, 2017, ECF No. 27, and, together with the above named Plaintiffs, the court refers to these parties as "Respondents."
The Respondents challenge four aspects of Commerce's final determination. See Pls. & Pl.-Intervenor's Mem. Supp. Rule 56.2 Mot. J. Agency R., June 5, 2017, ECF No. 38-2 ("Respondents' Br."). First, the Respondents challenge as not in accordance *1334with law and unsupported by substantial evidence Commerce's differential pricing analysis. Id. at 7-35. Second, the Respondents challenge Commerce's selection of surrogate value data sources to value head and shell byproducts, frozen shrimp, and ice. Id. at 35-43. Third, the Respondents challenge Commerce's decision to deny a byproduct offset for revenue from excess or scrap packaging. Id. at 43-45. Fourth, the Respondents challenge as not in accordance with law and unsupported by substantial evidence Commerce's calculation of the all-others separate rate. Id. at 45-46.
Mazzetta Company, LLC ("Mazzetta"), an importer of subject merchandise, challenges two aspects of Commerce's final determination. See Mem. Consol.-Pl. [Mazzetta] in Supp. Mot. J. Agency R. Pursuant Rule 56.2, June 5, 2017, ECF No. 39-1 ("Mazzetta Br."). First, Mazzetta argues that Commerce improperly omitted from the record documentation and memoranda memorializing the events that it claims led to the rescission of Commerce's review of Minh Phu Seafood Corporation, Minh Qui Seafood Co., Ltd., Minh Phat Seafood Co., Ltd., and Minh Phu Hau Giang Seafood Joint Stock Company (collectively, "Minh Phu Group" or "MPG"). See id. at 22-25; see also [ADD] Administrative Review of Certain Frozen Warmwater Shrimp from [Vietnam]: Selection of Respondents for Individual Examination at 7, PD 71, bar code 3273103-01 (Apr. 29, 2015) ("Resp't Selection Memo").3 Second, Mazzetta challenges as not in accordance with law and unsupported by substantial evidence Commerce's calculation of the all-others separate rate. See Mazzetta Br. at 25-43.
For the reasons that follow, the court sustains Commerce's application of the differential pricing analysis and calculation of the all-others rate, and Commerce's surrogate value data selections for head and shell byproduct and ice. The court also determines that Commerce fulfilled its statutory duty to maintain a complete and accurate administrative record. However, the court remands Commerce's surrogate value data selection for frozen shrimp, and Commerce's decision to deny an offset for packaging scrap revenue for further explanation or reconsideration consistent with this opinion.
BACKGROUND
Commerce initiated this tenth administrative review covering subject imports entered during the period of review ("POR"), February 1, 2014 through January 31, 2015. See Initiation of Antidumping and Countervailing Duty Administrative Reviews, 80 Fed. Reg. 18,202, 18,204 (Dep't Commerce Apr. 3, 2015). Commerce subsequently selected MPG and Soc Trang Seafood Joint Stock Company ("Stapimex") as mandatory respondents in this review. See Resp't Selection Memo at 9. Because Vietnam is a non-market-economy ("NME"), Commerce "begins with a rebuttable presumption that all companies within Vietnam are subject to government control." Final Decision Memo at 76. Based on this presumption, Commerce assigns all exporters of the subject merchandise in a NME country a single antidumping duty rate. Id. However, if an exporter can demonstrate the absence of government control, Commerce will calculate for it a separate rate. Id. Companies, other than the mandatory respondents, who are able to demonstrate the absence of government control are assigned the separate all-others rate. Id. Commerce has a practice of calculating the separate rate in the same manner as the all-others rate in investigations provided for in 19 U.S.C. § 1673d(c)(5). See Final Decision Memo at 62-63; see also Albemarle Corp. & Subsidiaries v. United States, 821 F.3d 1345, 1352-53 (Fed. Cir. 2016). Accordingly, the separate all-others rate is "an amount equal to the weighted average of the estimated weighted-average dumping margins established for exporters and producers individually investigated, excluding any zero and de minimis margins, and any margins determined entirely on the basis of facts available." Id. at 63.
Commerce published its preliminary results on March 10, 2016. See Certain Frozen Warmwater Shrimp From [Vietnam], 81 Fed. Reg. 12,702 (Dep't Commerce Mar. 10, 2016) (preliminary results of [ADD] administrative review and partial rescission of review; 2014-2015) ("Prelim. Results") and accompanying Decision Mem. for Preliminary Results of [ADD] Administrative Review: Certain Frozen Warmwater Shrimp from [Vietnam]; 2014-2015, A-552-802, PD 312, bar code 3446491-01 (Mar. 3, 2016) ("Prelim. Decision Memo"). Commerce preliminarily calculated weighted-average dumping margins of 2.86% for MPG, 4.78% for Stapimex, and 3.56% for all-other separate rate respondents. Prelim. Results, 81 Fed. Reg. at 12,703. Commerce applied its differential pricing analysis and determined that 78.00% of Stapimex's U.S. sales passed its Cohen's d test, that the Average-to-Average ("A-to-A") methodology could not account for the price differences, and that application of the Average-to-Transaction ("A-to-T") methodology to all of Stapimex's U.S. sales was appropriate to calculate Stapimex's weighted-average dumping margin. Prelim.
*1335Decision Memo at 21. In the preliminary determination, Commerce also applied its differential pricing analysis to MPG and determined that 55.10% of MPG's U.S. sales passed its Cohen's d test, that the A-to-A methodology could not account for the price differences, and applied the A-to-T methodology to MPG's U.S. sales that passed the Cohen's d and the A-to-A methodology to the U.S. sales that did not. Id. at 20-21.
On July 22, 2016, Commerce rescinded its review of MPG, one of the mandatory respondents.4 See Certain Frozen Warmwater Shrimp From [Vietnam], 81 Fed. Reg. 47,758 (Dep't Commerce July 22, 2016) (partial rescission of [ADD] administrative reviews (2014-2015; 2015-2016) and compromise of outstanding claims) ("Rescission Notice"). Following the rescission, the Respondents and Mazzetta submitted supplemental briefing to Commerce, arguing that Commerce should continue to rely on the weighted-average dumping margins calculated for both Stapimex and MPG to calculate the all-others rate. See [Enclosed] Suppl. Case Br. on Behalf of VASEP & its Non-Mandatory Resp't Members at 1-5, PD 348, bar code 3498415-01 (Aug. 16, 2016); [Mazzetta] Additional Briefing at 2-8, PD 349, bar code 3498417-01 (Aug. 16, 2016). In its final determination, Commerce continued to calculate a weighted-average dumping margin of 4.78% for Stapimex. Final Results, 81 Fed. Reg. at 62,718. However, as a result of the rescission, no rate was calculated for MPG and Commerce assigned Stapimex's rate as the all-others rate. See id. The court held oral argument on the issues raised by this action on April 30, 2018. See Oral Arg., Apr. 30, 2018, ECF No. 68.
JURISDICTION AND STANDARD OF REVIEW
The court has jurisdiction pursuant to 19 U.S.C. § 1516a(a)(2)(B)(iii) and 28 U.S.C. § 1581(c) (2012), which grant the court authority to review actions contesting the final determination in an administrative review of an antidumping duty order. The court will uphold Commerce's determination unless it is "unsupported by substantial evidence on the record, or otherwise not in accordance with law." 19 U.S.C. § 1516a(b)(1)(B)(i).
DISCUSSION
I. Application of Commerce's Differential Pricing Analysis
The Respondents challenge Commerce's differential pricing analysis as contrary to law and not supported by substantial evidence. See Respondents' Br. at 13-35. Specifically, they argue that Commerce's application of the differential pricing analysis does not identify whether a price difference is significant, see id. 13-22, does not effectuate the statutory purpose of 19 U.S.C. § 1677f-1(d)(B)(1)(i), id. at 22-31, and that Commerce unreasonably excludes the test sales from the comparison group. See id. 31-35. Defendant argues that Commerce's application of the differential pricing analysis is settled law and its application is supported by substantial evidence. See Def.'s Resp. Opp'n Pls.' Rule 56.2 Mots. J. Agency R. at 31-39, Nov. 21, 2017, ECF No. 51 ("Def.'s Resp. Br."). For the following reasons, Commerce's application of the differential pricing analysis is in *1336accordance with law, is supported by substantial evidence and is sustained.
In investigations, Commerce ordinarily uses the A-to-A methodology to calculate dumping margins.5 See 19 U.S.C. § 1677f-1(d)(1)(A) ; 19 C.F.R. § 351.414(c)(i) (2015).6 However, Commerce may use the alternative A-to-T methodology to calculate weighted-average dumping margins where: (i) Commerce finds a pattern of export prices for comparable merchandise that differ significantly among purchasers, regions, or periods of time, and (ii) Commerce explains why such differences cannot be taken into account using the standard A-to-A methodology. 19 U.S.C. § 1677f-1(d)(1)(B)(i)-(ii). Commerce has, through practice, adopted the same basis for applying its A-to-T methodology in administrative reviews. See JBF RAK LLC v. United States, 790 F.3d 1358, 1364 (Fed. Cir. 2015).7 The statute is silent as to how Commerce is to determine whether a pattern of significant price differences exists. However, the Statement of Administrative Action ("SAA"), which is "an authoritative expression by the United States concerning the interpretation and application" of the Uruguay Rounds Agreement Act, provides guidance. 19 U.S.C. § 3512(d). In relevant part, the SAA states that
the reluctance to use an average-to-average methodology has been based on a concern that such a methodology could conceal "targeted dumping." In such situations, an exporter may sell at a dumped price to particular customers or regions, while selling at higher prices to other customers or regions.... New section 777A(d)(1)(B) provides for a comparison of average normal values to individual export prices or constructed export prices in situations where an average-to-average or transaction-to-transaction methodology cannot account for a pattern of prices that differ significantly among purchasers, regions, or time periods, i.e., where targeted dumping may be occurring. Before relying on this methodology, however, Commerce must establish and provide an explanation why it cannot account for such differences through the use of an average-to-average or transaction-to-transaction comparison. In addition, the Administration intends that in determining whether a pattern of significant price differences exist. Commerce will proceed on a case-by-case basis, because small differences may be significant for one industry or one type of product, but not for another.
Uruguay Round Agreements Act, Statement of Administrative Action, H.R. Doc. No. 103-316, vol. 1, at 842-43 (1994), reprinted in 1994 U.S.C.C.A.N. 4040, 4177-78.
The statute affords Commerce discretion in determining whether a pattern of *1337significant price differences exists. See Fujitsu General Ltd. v. U.S., 88 F.3d 1034, 1039 (Fed. Cir. 1996) ; Torrington Co. v. United States, 68 F.3d 1347, 1351 (Fed. Cir. 1995). Nonetheless, the court must address whether Commerce's methodological choice is reasonable and determine that Commerce's conclusions are supported by substantial evidence. See Motor Vehicle Mfrs. Ass'n of U.S. v. State Farm Mut. Auto. Ins. Co., 463 U.S. 29, 48-49, 103 S.Ct. 2856, 77 L.Ed.2d 443 (1983) ("[A]n agency must cogently explain why it has exercised its discretion in a given manner."); see Smith-Corona Grp. v. United States, 713 F.2d 1568, 1571 (Fed. Cir. 1983), cert. denied, 465 U.S. 1022, 104 S.Ct. 1274, 79 L.Ed.2d 679 (1984) ; Fujitsu Gen. Ltd., 88 F.3d at 1039 (granting Commerce significant deference in determinations "involv[ing] complex economic and accounting decisions of a technical nature"); Ceramica Regiomontana, S.A. v. United States, 10 CIT 399, 404-05, 636 F.Supp. 961, 966 (1986), aff'd, 810 F.2d 1137, 1139 (Fed. Cir. 1987).
Commerce determines whether a pattern of significant price differences exists among purchasers, regions, or periods of time with the differential pricing analysis. See Final Decision Memo at 8. First, Commerce applies what it refers to as the "Cohen's d test," which measures the degree of price disparity between two groups of sales. See id. at 8-9. Commerce calculates the number of standard deviations by which the weighted-average net prices of U.S. sales for a particular purchaser, region, or time period (the "test group") differ from the weighted-average net prices of all other U.S. sales of comparable merchandise (the "comparison group").8 See id. at 9. The result of this calculation is a coefficient. See id. To arrive at the coefficient, Commerce divides the difference in the means of the net prices of the test group and comparison group by the pooled standard deviation.9 See id. at 19 n.68 (reproducing the formula). The coefficient is the number of standard deviations by which the weighted-average of the comparison group and the test group differ.10 See Prelim. Decision Memo at 19. A group of sales with a coefficient equal to or greater than 0.8 is said to "pass" the test, which signifies to Commerce that a significant *1338pattern of price differences exists within that group of sales. See id.; Final Decision Memo at 9. Commerce then relies on the "ratio test" to measure the extent of significant price differences. See Final Decision Memo at 8. The "ratio test" compares the combined value of sales that passed the Cohen's d test with the value of all sales. See Prelim. Decision Memo at 19-20. If the value of sales that passed the test accounts for 66% or more of a respondent's total sales, that indicates to Commerce that the pattern of significant price differences warrants application of the A-to-T method to all sales. See id. However, if the value of sales that passed the Cohen's d test is less than 66%, but more than 33%, Commerce takes a hybrid approach, applying the A-to-T method to the sales that passed its Cohen's d test and applying the A-to-A method to all other sales. See id. Alternatively, Commerce will apply the A-to-A method to all sales if 33% or less of a respondent's total sales passed its Cohen's d test. Id. at 20. Finally, Commerce applies the "meaningful difference" test, pursuant to which Commerce evaluates whether the difference between the weighted-average dumping margins calculated by the A-to-A method is "meaningfully" different than the weighted-average dumping margins calculated by the A-to-T method.11 Id. at 21.
Commerce's differential pricing analysis, as applied, constitutes a reasonable methodology for identifying patterns of prices that differ significantly and is therefore in accordance with law. As applied by Commerce, this tool measures "the extent to which the net prices to a particular purchaser, region, or time period [i.e., the test group] differ significantly from the net prices of all other sales of comparable merchandise [i.e., the base or comparison group]."12 Prelim. Decision Memo at 8; see Final Decision Memo at 8-9.
Further, it is reasonable for Commerce to apply its differential pricing analysis to determine whether a pattern exists for an individual exporter based on the exporter's purchasers, regions, or time period. The SAA specifically speaks to individual exporters' behavior that may result in masked targeted dumping and suggests that the methodology constructed by Commerce can look for patterns in individual exporter's actions. See SAA at 843, 1994 U.S.C.C.A.N. at 4178. Moreover, the SAA's explanation that "Commerce will proceed on a case-by-case" to determine whether the price differences are significant, see SAA at 843, 1994 U.S.C.C.A.N. at 4178, does not mandate that Commerce amend the test at every application. Instead, it is enough that the resulting methodology is able to detect differences of significant variances across a variety of cases.
The Respondents claim that the SAA demonstrates Congress' intent for Commerce to "tailor" its analysis to the different industry or product under investigation *1339or review, and to not indiscriminately apply the same test across all cases. See Respondents' Br. at 24.13 The Respondents point to nothing in the statute that requires Commerce to construct such a test. In this regard, the Respondents also argue that Commerce's determination is not supported by substantial evidence. See id. at 27-30. However, the Respondents' arguments are derivative of their contrary to law challenges. Specifically, they argue that Commerce's final determination is not supported by substantial evidence because the statute requires Commerce to consider information regarding a specific product or industry in running the differential pricing analysis, and Commerce's analysis does not. Commerce, however, was not required to consider industry-wide information and the Respondents' argument does not demonstrate that what Commerce did was unreasonable.
The Respondents also argue that Commerce's differential pricing analysis does not demonstrate that the price differences are of "practical" significance. See Respondents' Br. at 15-19. Specifically, the Respondents contend that the threshold categories of "small," "medium," and "large" are arbitrary because the differences they quantify are not informed by industry trends.14 See id. Here, the Respondents placed on the record, and addressed directly in their brief to the agency, documents evidencing volatilities in the shrimp and seafood prices in Vietnam.15 See, e.g., *1340VASEP Submission of Factual Info. on Differential Pricing at Ex. 35, PD 274, bar code 3308867-05 (Sept. 25, 2015); VASEP Submission of Factual Info. on Differential Pricing at Exs. 37-42, 44-45, PD 276-77, bar codes 3308867-07-08 (Sept. 25, 2015); Case Br. [to the Agency] on Behalf of [the] Respondents at 29-33, PD 330, bar code 3463452-01 (Apr. 25, 2016). The Respondents contend that Commerce's failure to address industry-specific data rendered the agency unable to evaluate whether a coefficient of 0.8 or higher (Commerce's threshold for a "large" price difference) was practically significant. See Respondents' Br. at 27-28. The Respondents' argument is unpersuasive because it assumes that Commerce is required to take into account pricing trends in the shrimp and seafood industries. However, as explained above, Commerce's application of the differential pricing analysis to individual exporters, without consideration of the industry at large, is a reasonable way of assessing whether a pattern of significant price differences exists.16
The Respondents argue that Commerce's methodology unreasonably focuses on internal variances within a respondent's prices. See Respondents' Br. at 13-15. To illustrate their argument, the Respondents provide three sets of numbers for which there is a standard deviation of 1.58, but which represent a 0.158%, 1.58%, and 15.8% deviation from the mean as to their respective number sets. Id. at 14. The Respondents contend that Commerce's analysis "completely overlook[s]" such "differences in magnitude." Id. In the final determination, Commerce explained that its differential pricing analysis is reasonable because it looks at price variances in the context of the two means. See Final Decision Memo at 20. Specifically, Commerce explained that, "[w]hen there is little variation in prices, then a small difference in the mean prices between the two groups may be significant where it would not be significant if the variation in prices were greater." Id. Commerce's explanation addresses the Respondents' challenge. Commerce's methodology evaluates whether the price variance is significant as compared to the actual prices at issue, and not as compared to some other set of prices. The statute allows Commerce to look at individual pricing behavior. See 19 U.S.C. § 1677f-1(d)(B)(1)(i). As a result, it is reasonable for Commerce to determine whether the price variance is significant relative to a respondent's own pricing behavior in the United States market.
The Respondents also argue that Commerce's exclusion of test group sales from *1341the comparison group sales is not in accordance with law because Commerce's methodology leads to distortions in the dumping comparison and alters what constitutes "normal" pricing behavior. See Respondents' Br. at 31-35; see also Pls. & Pl.-Intervenor's Reply Supp. Rule 56.2 Mot. J. Agency R. at 5, Jan. 22, 2018, ECF No. 59 ("Respondents' Reply"). In the final determination, Commerce explained that including test group sales in the comparison group "would result in the sales prices of purchasers, regions or time periods being compared to themselves." Final Decision Memo at 37. Commerce's explanation is reasonable. Respondents' argument presents an alternative methodology, but does not demonstrate that there is anything unreasonable with the way Commerce approaches the test and comparison groups.
II. Memoranda Regarding the WTO Dispute Settlement Agreement Discussions
Mazzetta argues that Commerce failed to place on the administrative record documents memorializing ex parte discussions from a World Trade Organization ("WTO") dispute settlement agreement reached between the governments of Vietnam and the United States ("WTO Settlement Agreement").17 See Mazzetta's Br. at 22-25. Defendant argues that the WTO proceedings do not constitute ex parte meetings because they were not conducted "pursuant" to the tenth administrative review. Def.'s Resp. Br. at 27. Defendant contends that Commerce is only required to produce and place upon the record information it obtains pursuant to the review and "not any information obtained by Commerce during the period of time coterminous with the initiation and conclusion of the review." Id. at 29 (citing 19 U.S.C. § 1516a(b)(2)(A) ; 19 C.F.R. § 351.104(a)(1) ). The Defendant-Intervenor argues that Mazzetta is improperly seeking to enlarge the administrative record, which it cannot do in a USCIT Rule 56.2 motion, see Def.-Intervenor Ad Hoc Shrimp Trade Action Comm.'s Resp. Pl.'s & Pl.-Intervenor's & Consol. Pl.'s Mots. J. Agency R. Under USCIT Rule 56.2 at 11 - 16, Nov. 21, 2017, ECF No. 50 ("Def.-Intervenor's Resp. Br."), and that Commerce's decision to rescind and its calculation of the all-others rate is supported by substantial evidence on the record before the court.18 Id. at 19-27. For the reasons *1342that follow, the court will not require Commerce to place any additional information on the record.
The applicable statute provides that Commerce
shall maintain a record of any ex parte meeting between-
(A) interested parties or other persons providing factual information in connection with a proceeding, and
(B) the person charged with making the determination, or any person charged with making a final recommendation to that person, in connection with that proceeding,
if information relating to that proceeding was presented or discussed at such meeting. The record of such an ex parte meeting shall include the identity of the persons present at the meeting, the date, time, and place of the meeting, and a summary of the matters discussed or submitted. The record of the ex parte meeting shall be included in the record of the proceeding.
19 U.S.C. § 1677f(a)(3).19
To trigger the disclosure requirements of 19 U.S.C. § 1677f(a)(3), there must be a meeting (i) between "persons providing factual information in connection with a proceeding ... and the person charged with making the determination" and (ii) "information relating to that proceeding [must be] presented or discussed at such [a] meeting." 19 U.S.C. § 1677f(a)(3).20 Parties cannot rely upon *1343speculation that ex parte communications occurred, but must establish that a reasonable basis exists to believe that the administrative record is incomplete. See Sachs Auto. Prod. Co. v. United States, 17 CIT 290, 292-93, 1993 WL 135845 (1993) ; Saha Thai Steel Pipe Co. v. United States, 11 CIT 257, 261-62, 661 F.Supp. 1198, 1202-03 (1987) ; see also CSC Sugar LLC v. United States, 42 CIT ----, ----, Slip Op. 18-64 at 8, 317 F.Supp.3d 1334, 1339, 2018 WL 2670715 (June 1, 2018) (taking judicial notice of a newspaper article to find a "reasonable basis to believe [that] the record [wa]s incomplete.").
Commerce was not required to place memoranda relating to the WTO dispute negotiations proceedings on the record.21 Here, Mazzetta argues that Commerce met with "persons," specifically, the government of Vietnam. See Mazzetta's Br. at 23-24. However, Mazzetta incorrectly states that Commerce relied upon the "meetings and agreement" as "justification for rescinding the review of Minh Phu Group[.]" See id. at 23. Commerce did not rely upon the "meetings and agreement" as "justification for rescinding the review of Minh Phu Group." The sole basis for rescinding the review was that rescission was sought by all the parties who had requested review. See Rescission Notice, 81 Fed. Reg. at 47,758. In fact, the regulations providing for rescission do not require any rationale for rescission other than that rescission was requested.22 Although Commerce stated that the parties sought the rescission because of the settlement that was reached at the WTO, Commerce did not base its decision to rescind on the substance of that settlement agreement. Instead, Commerce concluded that, "because all parties that requested a review of the Minh Phu Group have withdrawn their requests, the Department is rescinding the review with respect to the Minh Phu Group ...." Id.
The only decision that Mazzetta's argument implicates is Commerce's decision to extend the deadline to request rescission of the review. The rationale given by each of the parties seeking an extension, and by Commerce granting the extension was that "[a] mutually satisfactory resolution of these disputes was not effectuated within 90 days of the date of publication of the notice of initiation of the requested review."23 Rescission *1344Notice, 81 Fed. Reg. at 47,758. There is no claim that Commerce based its decision to extend the deadline on the contents of the WTO Settlement Agreement or the discussions leading up to it. The relevant factor, as stated by the parties seeking an extension to submit a request to rescind the review, and by Commerce in granting the extension, was the timing of the settlement at the WTO, not the resulting settlement's substance. Id. The record is therefore complete as to why Commerce granted the parties' requests, and Mazzetta has failed to set forth facts to establish a reasonable basis for determining that the record is incomplete. Mazzetta assumes that the substance of the WTO Settlement Agreement led to the rescission, and therefore concludes that there must have been ex parte discussions that would have affected Commerce's decision. Mazzetta's assumption is simply incorrect, since nothing more is required for a rescission other than a request. See generally 19 C.F.R. § 351.213(d)(1). Therefore, Mazzetta has only speculated that "information relating to [the] proceeding was presented or discussed" at the WTO.
III. The Rescission of MPG's Review and the Calculation of the All-Others Rate
Mazzetta challenges Commerce's calculation of the all-others rate, on the grounds that Commerce's decision to rescind the review as to MPG was contrary to law and not supported by substantial evidence,24 and that, even if it was proper to rescind the review as to MPG, Commerce should nonetheless have still used MPG's rate from the preliminary determination in calculating the all-others rate. See Mazzetta's Br. at 25-43; see also Reply Br. Consol.-Pl. [Mazzetta] in Supp. Mot. J. Upon. Agency R. Pursuant to Rule 56.2 at 1 - 8, Jan. 22, 2018, ECF No. 58. Defendant argues that Commerce's decision to rescind was reasonable, consistent with past practice, and supported by substantial evidence because it was based on the same grounds proffered by the parties requesting rescission.25 Def.'s Resp. Br. at 23-26. Further, Defendant argues that Commerce's calculation of the all-others rate was based on a permissible interpretation *1345of the statute and that Mazzetta wrongfully attempts to read into the statute a representativeness requirement. See id. at 17-23. For the reasons that follow, Commerce's decisions to rescind the administrative review of MPG and to calculate the all-others rate using solely Stapimex's rate are sustained.
A. Rescission
Pursuant to regulation, Commerce "will rescind an administrative review ..., in whole or in part, if a party that requested a review withdraws the request within 90 days of the date of publication of notice of initiation of the requested review." See 19 C.F.R. § 351.213(d)(1). The agency may extend this 90-day deadline for rescission if it "decides that it is reasonable to do so."26 Id. Here, all requests to review MPG were withdrawn more than 90 days after the publication of the notice of initiation of this review. See Rescission Notice, 81 Fed. Reg. at 47,758. In the Rescission Notice, Commerce explained that the parties had reported that a "mutually satisfactory resolution" of two WTO disputes did not occur within 90-days of initiation of the tenth review and that rescission would aid the United States and Vietnamese governments in resolving those WTO matters.27 Id. The requesting parties explained that they could not foresee the need to rescind in the first 90-days of this review and that a rescission of the review would aid in implementation of the WTO Settlement Agreement. See [MPG]'s Withdrawal of AD Review Request, PD 335, bar code 3484285-01 (July 6, 2016); Domestic Producers' Partial Withdrawal of Request for Review, PD 336, bar code 3484291-01 (July 6, 2016); Am. Shrimp Processors Ass'n Partial Withdrawal of Request for Review, PD 337, bar code 3484301-01 (July 6, 2016). Commerce explained that, under these circumstances, it found it reasonable to extend the rescission deadline and that, because all requests to review MPG had been withdrawn, the agency would rescind the review as to MPG.28 Id. Commerce's regulations allow for rescission, in whole or in part, when the party requesting review withdraws its request. See 19 C.F.R. § 351.213(d)(1). Here, all requests to review MPG were withdrawn, *1346and Mazzetta points to nothing to undermine the reasonableness of Commerce's decision to extend the deadline to request rescission or to rescind.29 Commerce's decision is in accordance with law and is supported by substantial evidence.
B. Calculation of the All-Others Rate
Mazzetta argues that, even if it was proper to rescind the review as to MPG, Commerce should have included MPG's rate from the preliminary determination in its calculation of the all-others rate, rather than basing the all-others rate solely on the rate calculated for Stapimex, the remaining respondent.30 See Mazzetta's Br. at 25-43. In an antidumping investigation or administrative review, if it is not "practicable" for Commerce to review or investigate each known exporter or producer, Commerce may limit its examination to a "reasonable number of exporters or producers" and determine weighted-average dumping margins only for those selected. 19 U.S.C. § 1677f-1(c)(2). The statute provides Commerce with two options for examination in such cases: it can either select "exporters and producers accounting for the largest volume of the subject merchandise from the exporting country that can be reasonably examined," 19 U.S.C. § 1677f-1(c)(2)(B), or examine a statistically representative "sample of exporters, producers, or types of products[.]" 19 U.S.C. § 1677f-1(c)(2)(A). The SAA explains that when Commerce employs the latter sampling method, it will "select the most representative sample at the early stages of the investigation or review," based on the information known to Commerce at that point in time. See SAA at 873, 1994 U.S.C.C.A.N. at 4201 (emphasis omitted). By practice, Commerce calculates a rate for the separate rate applicants pursuant to 19 U.S.C. § 1673d(c)(5). See Albemarle Corp. & Subsidiaries v. United States, 821 F.3d 1345, 1352-53 (Fed. Cir. 2016). Section 1673d(c)(5) provides a method to calculate the all-others rate and states that the all-others rate shall be the weighted average of the individually investigated exporter's and producer's dumping margins, excluding any margins that are de minimis, zero or determined entirely by application of an adverse inference. See 19 U.S.C. § 1673d(c)(5).31
*1347In the final determination, Commerce explained its practice to assign to the separate rate respondents the all-others rate pursuant to 19 U.S.C. § 1673d(c)(5)(A). See Final Decision Memo at 62-63. Here, following the rescission of the review as to MPG, only one mandatory respondent, Stapimex, remained under review. Commerce explained that, as neither 19 U.S.C. § 1673d(c)(5)(A) nor 19 U.S.C. § 1677f-1(c)(1) address how Commerce is to calculate a rate for the separate rate respondents following either the rescission of a review or when only one mandatory respondent is examined, it followed its practice and assigned as the all-others rate the only remaining calculated rate that was neither de minimis nor the result of applying an adverse inference. Id. at 63-64. Further, Commerce explained that, prior to rescinding the review, it did not calculate a final dumping margin for MPG and only had before it MPG's sales and factors of production ("FOP") data that was collected and verified for the preliminary determination. Id. at 64. Accordingly, it assigned Stapimex's rate, the only remaining above de minimis rate, as the all-others rate. See id. at 63-64.
Commerce reasonably based the all-others rate on the rate of the only remaining respondent in the review, Stapimex. Nothing in the statutory framework requires Commerce to calculate the all-others rate using multiple rates nor precludes Commerce from relying on just one rate. Mazzetta argues that, because 19 U.S.C. § 1677f-1(c) and 19 U.S.C. § 1673d(c)(1)(B), (c)(5) consistently use the plural "exporters" and "producers" to refer to the individually investigated respondents, the all-others rate must be based on the rates of multiple respondents. See Mazzetta Br. at 26-27. Under the largest volume exception, however, Commerce may choose to investigate only one exporter or producer, in which case there would not be multiple established rates. See 19 U.S.C. § 1677f-1(c)(2). The statute simply provides for the possibility of Commerce having multiple established rates at the end of a given investigation or review; it does not necessitate the calculation of an all-others rate using multiple respondents' rates at the end of every investigation or review. Further, the language of 19 U.S.C. § 1673d(c)(5)(B) that guides Commerce's actions when an established rate is zero, de minimis, or based entirely on an adverse inference, likewise uses the plural "exporters and producers." It is nevertheless possible that, if any one or all three of those circumstances occur, Commerce can be left with only one respondent. Mazzetta's construction of the statute, however, would imply that Commerce could not rely on just one respondent's rate, while in fact the statute envisions cases when that may happen.
Mazzetta also argues that the statutory framework requires the resulting all-others rate to be representative, which requires it to be based on multiple rates, where available. See Mazzetta's Br. at 27-29. The all-others rate here is representative. As explained above, the SAA directs Commerce to narrow its review or investigation to respondents able to provide a representative sample. See SAA at 872-73, 1994 U.S.C.C.A.N. at 4200-01. Mazzetta does not challenge the original selection of mandatory respondents for the tenth administrative review. It is not an unforeseeable occurrence for Commerce, at the end of an investigation or administrative review, to be left with only one respondent.
*1348The loss of a respondent does not automatically mean that the resulting all-others rate is not representative. If that was the case, the exception in 19 U.S.C. § 1673d(c)(5)(B) would not exist.32
IV. Commerce's Analysis of Specific Surrogate Values
The Respondents challenge Commerce's surrogate value data selections for head and shell byproduct, frozen shrimp, and ice. See Respondents' Br. at 35-43. Defendant refutes all of these challenges and argues that Commerce's final determination should be sustained in all respects. See Def.'s Resp. Br. at 39-41, 42-52. For the reasons that follow, the court sustains Commerce's surrogate value selections for head and shell byproduct and ice. However, the court remands Commerce's surrogate value data selection for frozen shrimp for further explanation and consideration.
A. Legal Framework
In antidumping proceedings involving NMEs,33 Commerce generally calculates normal value using the FOPs used to produce the subject merchandise and other costs and expenses. 19 U.S.C. § 1677b(c)(1). Commerce will value respondents' FOPs using the "best available information regarding the values of such factors in a market economy country or countries considered to be appropriate by [Commerce]." 19 U.S.C. § 1677b(c)(1)(B). To the extent possible, Commerce uses FOPs from market economy countries that are: "(A) at a level of economic development comparable to that of the nonmarket economy country, and (B) significant producers of comparable merchandise." 19 U.S.C. § 1677b(c)(4). Commerce's regulatory preference is to "value all factors in a single surrogate country." 19 C.F.R. § 351.408(c)(2).
Commerce's methodology for selecting the best available information evaluates data sources based upon their: (1) specificity to the input; (2) tax and import duty exclusivity; (3) contemporaneity with the period of review; (4) representativeness of a broad market average; and (5) public *1349availability. See Import Admin., U.S. Dep't Commerce, Non-Market Economy Surrogate Country Selection Process, Policy Bulletin 04.1 (Mar. 1, 2004), available at http://ia.ita.doc.gov/policy/bull04-1.html (last visited June 18, 2018); Final Decision Memo at 54-55. Commerce uses the same methodology to calculate the surrogate value of byproducts generated during the production process, and offsets production costs incurred by a respondent by the value of those byproducts. See Final Decision Memo at 46-47, 50; see also Tianjin Magnesium Int'l Co. v. United States, 34 CIT 980, 993, 722 F.Supp.2d 1322, 1336 (2010) ; Guangdong Chems. Imp. & Exp. Corp. v. United States, 30 CIT 1412, 1422-23, 460 F.Supp.2d 1365, 1373-74 (2006).
B. Head and Shell Byproducts
The Respondents challenge Commerce's use of the Indian Global Trade Atlas ("GTA") import data for subheading 0508.00.50, Harmonized Tariff Schedule ("HTS"), to value head and shell byproducts, and argue that Commerce should have instead used Bangladeshi UN Comtrade import data covering HTS 0508.00. See Respondents' Br. at 35-39; see also Final Decision Memo at 57-59; [Petitioner's] [Surrogate Value] Comments at 2, Ex. 2, PD 232, bar code 3297256-01 (Aug. 10, 2015) ("Indian GTA Shell & Head data"); [VASEP] [Surrogate Value] Submission at Ex. 3, PD 235, bar code 3297559-02 (Aug. 10, 2015) ("Bangladeshi UN Comtrade Shell & Head data"). Defendant contends that Commerce's decision to use Indian GTA Shell & Head data to value head and shell byproduct is supported by substantial evidence and is in accordance with law. See Def.'s Resp. Br. at 48-52. The court agrees with Defendant.
Commerce's decision to use Indian GTA Shell & Head data to value head and shell byproduct is supported by substantial evidence. Commerce found the Indian GTA Head & Shell data to be contemporaneous, publicly available, representative of a broad market average, and tax and duty exclusive. Final Decision Memo at 57-58. Commerce also explained that the Bangladeshi UN Comtrade Head & Shell data valued the whole shrimp at a lower cost than its waste byproduct, i.e., the shell and head. Id. at 58. Although the Respondents claim that Commerce should not have defaulted to rejecting the Bangladeshi UN Comtrade Shell & Head data for HTS 0508.00 over capping it because the byproduct value exceeded that of the whole, see Respondents' Br. at 38, Commerce's decision to reject the data is within its discretion.
The Respondents also argue that Commerce did not adequately explain its reasoning for rejecting the Bangladeshi data. See Respondents' Br. at 36-37; see also Respondents' Reply at 20-22. Specifically, they challenge Commerce's explanation that it was unable to evaluate the appropriateness of the Bangladeshi UN Comtrade Head & Shell data because it lacked a written description, yet relied on Bangladeshi UN Comtrade data for a different HTS category of the same level of descriptiveness to value ice.34 See Respondents'
*1350Br. at 36-37; see also Respondents' Reply at 20-22. However, Commerce's reasoning for rejecting the Bangladeshi UN Comtrade Head & Shell data is not based solely on a missing description. In the final determination, Commerce explained that it had before it a six-digit Bangladeshi UN Comtrade Head & Shell HTS number and an eight-digit Indian GTA Head & Shell HTS number, and that without a written description it "logically" determined that the latter was more specific than the former. Final Decision Memo at 58. Further, as explained above, Commerce exercised its discretion and rejected the data source because the relative value of the byproduct exceeded the value of the main input, i.e., whole shrimp.35
C. Frozen Shrimp
The Respondents challenge as contrary to law and unsupported by substantial evidence Commerce's valuation of the frozen shrimp input using Bangladeshi UN Comtrade data for HTS 0306.13. See Respondents' Br. 39-41. Defendant argues that Commerce's use of the Bangladeshi data is reasonable and constitutes the best available information to value the input because the data is from the primary surrogate country. Def.'s Resp. Br. at 42-44. The court remands Commerce's determination because Commerce has failed to explain why it is reasonable to default to data from the primary surrogate country when that data is not contemporaneous and the record includes a more specific data source.
In the final determination, Commerce valued respondents' frozen warmwater shrimp input using Bangladeshi UN Comtrade data for HTS 0306.13, covering "Shrimps & prawns, whether/not in shell, frozen." See Final Decision Memo at 46-48. There were just two potential surrogate values on the record for this input: the Bangladeshi UN Comtrade data and the Indian GTA data. Id. at 46. Commerce explained that, since both the Bangladeshi UN Comtrade data and the Indian GTA data on the record are from basket categories, the agency would rely on the Bangladeshi data because it is from the primary surrogate country. See id. at 47. Commerce justified its use of the Bangladeshi data, which is not contemporaneous, over the Indian data, which is contemporaneous, by emphasizing its preference for data from the primary surrogate country. See id. At oral argument, Defendant and Defendant-Intervenor further explained that, in choosing between two basket categories, where both data sets are equally non-specific, primary surrogate country data is preferred. See Oral Arg. at 02:03:28-02:04:03.
Commerce's selection of the Bangladeshi data was not reasonable in light of evidence *1351that it is from a far less specific category than the Indian data. The Bangladeshi UN Comtrade data for HTS 0306.13 covers, "Shrimps & prawns, whether/not in shell, frozen." Surrogate Values for the Prelim. Results at Ex. 3e, PD 313, bar code 3446496-01 (Mar. 3, 2016). Forty-one percent of shipments covered by this data are from coldwater regions, even though coldwater shrimp is not used in the production of warmwater shrimp in Vietnam. See id. By comparison, the Indian GTA data for HTS 0306.17 covers "Shrimps & prawns, Frozen, Other Than Cold-Water" and is limited to warmwater shrimp. [Certain Frozen Warmwater Shrimp from Vietnam-ASPA's Surrogate Value] Comments at Ex. 1, PD 232, bar code 3297256-01 (Aug. 10, 2015).
Commerce has not explained why the Bangladeshi UN Comtrade data constitutes the best available information, in light of the record evidence that a percentage of the Bangladeshi UN Comtrade data includes coldwater shrimp. Commerce does not address the record evidence regarding the percentage of coldwater shrimp, except to say that "the nature of the underlying data of the countries included within the import statistics do not impact the Department's requirement to select the best available information on the record to value purchased semi-processed frozen shrimp with a frozen shrimp [surrogate value]." Final Decision Memo at 48. Further, by emphasizing that it prefers surrogate country data when the two HTS categories are basket categories, see id. at 47, Commerce simply restates a regulatory preference without supporting its decision with record evidence. Commerce has not explained why this preference is reasonable in light of evidence that the two data sets are not equally specific. Commerce's decision to value frozen shrimp using Bangladeshi UN Comtrade data is not reasonable based on this record, and is remanded to the agency for reconsideration or further explanation consistent with this opinion.
D. Ice
The Respondents challenge Commerce's selection of Bangladeshi UN Comtrade data covering HTS 2201.90 to value the respondents' ice input because it was not specific to the input, and argue that Commerce should have instead valued the input using ice cost data generated by Apex Foods Limited in 2013-2014 ("Apex 2013-2014 data"). See Respondents' Br. at 42-43; see also [VASEP] [Surrogate Value] Submission Ex. 4, PD 235, bar code 3297559-02 (Aug. 10, 2015). Defendant argues that Commerce's selection is in accordance with law and is supported by substantial evidence. See Def.'s Resp. Br. at 45-48. The court agrees with Defendant.
In the final determination, Commerce explained that Bangladeshi UN Comtrade Ice data constitutes the best information available to value ice because it is specific to respondents' input, publicly available, representative of a broad market average, and tax and duty exclusive. See Final Decision Memo at 53-55. Commerce acknowledged that the Bangladeshi UN Comtrade Ice data was not contemporaneous, but explained that it was nevertheless "superior" to the Apex 2013-2014 data which represented only the experience of a single shrimp producer in Bangladesh. Id. at 54.
The Respondents challenge Commerce's reliance on the Bangladeshi UN Comtrade Ice data because that HTS category includes a "patently inapplicable input data (i.e., snow)" and is not contemporaneous. Respondents' Br. at 42. However, Commerce explained that respondents did not contend that the ice covered by the Bangladeshi UN Comtrade data is different from the ice utilized by Stapimex and did *1352not provide Commerce with "an HTS number for the specific ice that Stapimex purchased," instead "offer[ing] a single financial statement upon which to rely for an ice [surrogate value]." Final Decision Memo at 55 (citation omitted). The Respondents have not explained why the Bangladeshi UN Comtrade Ice data is not specific to the ice input. Further, without more, the court cannot say that the selection of a source representing a broad market average, rather than a source specific to a single company, is unreasonable.36
V. Commerce's Denial of an Offset for Packaging Scrap
The Respondents challenge Commerce's decision to deny an offset for packaging scrap revenue and contend that the excess or scrap packaging should have been treated as all other byproducts. See Respondents' Br. at 43-45. Defendant argues that, in light of Commerce's discretion in this area and the fact that packaging scrap is not directly derived from the production of the subject merchandise, Commerce's decision was reasonable and lawful. See Def.'s Resp. Br. at 52-54. The court remands Commerce's decision because Commerce has not explained why its practice is reasonable.
Pursuant to the relevant statute, in an NME Commerce will calculate the normal value of a given product by valuing "the factors of production utilized in producing the good[.]" 19 U.S.C. § 1677b(c)(1)(A)-(B). The statute, however, does not direct how Commerce is to determine which products qualify for the byproduct offset and no regulation exists to fill the gap. In such a situation, Commerce has the discretion to set the standards by which items qualify for a byproduct offset, so long as Commerce's selection satisfies the overall purpose of the ADD statute, to calculate accurate dumping margins and is reasonable. See Rhone Poulenc, Inc. v. United States, 899 F.2d 1185, 1191 (Fed. Cir. 1990) ; see also QVD Food Co. v. United States, 658 F.3d 1318, 1323 (Fed. Cir. 2011).
In the final determination, Commerce declined to grant a byproduct offset for packaging materials that either contained the raw materials used to produce the subject merchandise or were purchased, but not used, to pack the subject merchandise. See Final Decision Memo at 67-68. Commerce explained that it denied the offset because pursuant to its practice an offset is granted only for byproducts that are generated in relation to, or as a result of, the production of the subject merchandise.37 See id. Commerce, however, does *1353not offer an explanation for why its practice is reasonable and justifies its denial of the byproduct offset by reiterating its practice, citing to prior determinations where the practice was applied, and stating that the excess/scrap packaging at issue is not a byproduct. See id. The court reviewed the prior determinations to which Commerce cites, however, none of these determinations explain why the practice was adopted or why it is reasonable in light of the relevant statute.38
The statutory language does not exclude the possibility that scrap packaging would be utilized in the production of a good. The statute calculates the normal value of a good based on the factors of production involved in producing the subject merchandise. See 19 U.S.C. § 1677b(c)(1)(A)-(B). Presumably, the value of the factor of production at issue here includes its packaging. Commerce may have a rationale for excluding packaging as a byproduct, but that rationale is not reasonably discernable and Commerce has not stated it.39 Therefore, Commerce's decision to deny an offset for excess/scrap packaging is remanded to the agency for reconsideration or further explanation consistent with this opinion.
CONCLUSION
For the foregoing reasons, the court remands Commerce's surrogate value data selection for frozen shrimp, and sustains the Final Results in all other respects. Accordingly, it is
ORDERED that Commerce's decision to value frozen shrimp using Bangladeshi UN Comtrade data for HTS 0306.13 is *1354remanded for reconsideration or further explanation consistent with this opinion; and it is further
ORDERED that Commerce's decision to deny an offset for excess/scrap packaging is remanded for reconsideration or further explanation consistent with this opinion; and it is further
ORDERED that Commerce shall file its remand redetermination with the court within 60 days of this date; and it is further
ORDERED that the parties shall have 30 days thereafter to file comments on the remand redetermination; and it is further
ORDERED that the parties shall have 30 days to file their replies to comments on the remand redetermination.