with respect to such product is attributable to domestic producers which are represented in such petition. (4) Measurement (A) In general For purposes of determining whether the total annual domestic production requirement under paragraph (3) has been satisfied, the petitioners may elect whether such determination shall be made on the basis of— (i) net tons of production during the preceding year, or (ii) net monetary value of sales of the product during the preceding year. (B) Treatment of trade organizations For purposes of subparagraph (A), in the case of a trade organization described in paragraph (2)(B), the total annual domestic production attributable to any domestic producer which is part of such organization shall be included for purposes of determining whether the requirement under such subparagraph has been satisfied. (C) Treatment of labor unions and individuals For purposes of subparagraph (A), in the case of a labor union described in paragraph (2)(C) or individuals described in paragraph (2)(D) (referred to in this subparagraph as petitioning employees ), the total annual domestic production attributable to such labor union or the petitioning employees shall be determined based on— (i) the total production of the product during the preceding year by any producer that employs members of such labor union or petitioning employees, and (ii) the percentage of the total number of employees of such producers during the preceding year who are members of such labor union or petitioning employees. (D) Exclusion of double counting In the case of more than 1 eligible entity which is included in a petition, the Secretary shall ensure that any production attributable to each such eligible entity is not included in the determination under paragraph (3) more than once. (5) Petition With respect to any product, the petition described in paragraph (1) shall include— (A) the applicable HTS code with respect to such product, (B) the eligible entities and the percentage of domestic production represented by such