D.C. Mun. Regs. tit. 9, § 3900
3900.1 The provisions of this chapter are adopted under authority of D.C. Official Code § 47-5109(2).
3900.2 The provisions of this chapter shall be in effect with respect to taxable years commencing after December 31, 2018.
SOURCE: Final Rulemaking published at 67 DCR 1234 (February 7, 2020).