2 (1964). Once the Commissioner has imposed a change in accounting method, the application of IRC § 481(a) to such change is mandatory. Primo Pants, Emert v. Commissioner, T.C. Memo. 1999-175, Hitachi Sales Corp. of America. http://news.bna.conYden/clisplaybateh_print_display.adp 7/9 EFTA_R1_0212466