Sec. 51.511  Forward-looking economic cost per unit.

    (a) The forward-looking economic cost per unit of an element equals 
the forward-looking economic cost of the element, as defined in 
Sec. 51.505, divided by a reasonable projection of the sum of the total 
number of units of the element that the incumbent LEC is likely to 
provide to requesting telecommunications carriers and the total number 
of units of the element that the incumbent LEC is likely to use in 
offering its own services, during a reasonable measuring period.
    (b)(1) With respect to elements that an incumbent LEC offers on a 
flat-rate basis, the number of units is defined as the discrete number 
of elements (e.g., local loops or local switch ports) that the incumbent 
LEC uses or provides.
    (2) With respect to elements that an incumbent LEC offers on a 
usage-sensitive basis, the number of units is defined as the unit of 
measurement of the usage (e.g., minutes of use or call-related database 
queries) of the element.