; or (ii) affect a particular group, industry, or sector of the economy. (c) Unified Agenda (1) Submission of regulations under development or review Not later than March 15 and September 15 of each year, the head of each agency shall submit to the Administrator an agenda of each regulation under development or review in accordance with any guidance issued under this section. Each agenda shall include, to the extent practicable, the following: (A) For each regulation— (i) a regulation identifier number; (ii) a brief summary of the regulation; (iii) a citation to the legal authority to issue the regulation; (iv) any legal deadline for the issuance of the regulation; (v) the name and phone number for a knowledgeable agency employee; and (vi) the stage of review for issuing the regulation. (B) For each regulation expected to be promulgated within the following 18 months— (i) a determination of whether the regulation is expected to be a significant regulatory action or an economically significant regulatory action; (ii) any available clear summary of the expected costs or benefits