Example. In 1995, X uses a bulldozer exclusively to clear the land on several adjacent real estate development projects, A, B, and C. A, B, and C are treated as separate units of property under the principles of § 1.263A-10 . X decides to allocate the basis of the bulldozer among the three projects on the basis of time. At the end of the first quarter of 1995, the production period has commenced for all three projects. The bulldozer was operated for 30 hours on project A, 80 hours on project B, and 10 hours on project C, for a total of 120 hours for the entire period. For purposes of determining accumulated production expenditures as of the end of the first quarter, 1/4 of the adjusted basis of the bulldozer is allocated to project A, 2/3 to project B, and 1/12 to project C. Nonworking hours, regularly scheduled nonworking days, or other periods in which the bulldozer is temporarily idle (within the meaning of § 1.263A-1(e)(3)(iii)(E) ) during the measurement period are not taken into account in allocating the basis of the bulldozer.
26 C.F.R. §1.263A-11