47 CFR § 1.1409 - Allocation of Unusable Space Costs.
(a) With respect to the formula referenced in § 1.1406(d)(2), a utility shall apportion the cost of providing unusable space on a pole so that such apportionment equals two-thirds of the costs of providing unusable space that would be allocated to such entity under an equal apportionment of such costs among all attaching entities.
(b) All attaching entities attached to the pole shall be counted for purposes of apportioning the cost of unusable space.
(c) Utilities may use the following rebuttable presumptive averages when calculating the number of attaching entities with respect to the formula referenced in § 1.1406(d)(2). For non-urbanized service areas (under 50,000 population), a presumptive average number of attaching entities of three. For urbanized service areas (50,000 or higher population), a presumptive average number of attaching entities of five. If any part of the utility's service area within the state has a designation of urbanized (50,000 or higher population) by the Bureau of Census, United States Department of Commerce, then all of that service area shall be designated as urbanized for purposes of determining the presumptive average number of attaching entities.
(d) A utility may establish its own presumptive average number of attaching entities for its urbanized and non-urbanized service area as follows:
(1) Each utility shall, upon request, provide all attaching entities and all entities seeking access the methodology and information upon which the utilities presumptive average number of attachers is based.
(2) Each utility is required to exercise good faith in establishing and updating its presumptive average number of attachers.
(3) The presumptive average number of attachers may be challenged by an attaching entity by submitting information demonstrating why the utility's presumptive average is incorrect. The attaching entity should also submit what it believes should be the presumptive average and the methodology used. Where a complete inspection is impractical, a statistically sound survey may be submitted.
(4) Upon successful challenge of the existing presumptive average number of attachers, the resulting data determined shall be used by the utility as the presumptive number of attachers within the rate formula.