The sales factor, except for transportation companies, is a fraction, the numerator of which is the total sales of the taxpayer in the District during the taxable year; and the denominator of which is the total sales of the taxpayer everywhere during the taxable year.
The sales factor, in the case of transportation companies, is a fraction, the numerator of which is the total revenue units first received by the company as originating or connecting traffic at a point within the District plus the total revenue units discharged or unloaded by the company at a point within the District at the termination of the transportation movement or for transfer to a connecting carrier; and the denominator of which is twice the total revenue units originated everywhere during the taxable year.
One (1) ton of freight shall constitute one (1) revenue unit; and ten (10) passengers shall constitute one (1) revenue unit.
If a transportation company's revenue is predominately from the transportation of passengers, the number of passengers loaded and discharged may be used in lieu of originating and terminating tonnage.
Except for transportation companies, sales other than sales of tangible personal property, are in the District if either of the following apply:
A sale of tangible personal property, including a sale to the United States government, shall be in the District, regardless of the point of passage of title, f.o.b. point, or other conditions of the sale, if any of the following factors apply:
For the purposes of this section, the word "sales" includes all receipts deemed to be business income not subject to allocation.
D.C. Mun. Regs. tit. 9, r. 9-128