29 C.F.R. § 4.177
(a) In general.
(b) Furnishing equivalent fringe benefits.
(c) Furnishing cash equivalents.
(5) In determining the hourly cash equivalent of those fringe benefits which are not stated in the determination in terms of a cash amount, but are stated, for example, as “nine paid holidays per year” or “1 week paid vacation after one year of service”, the employee's hourly monetary rate of pay is multiplied by the number of hours making up the paid holidays or vacation. Unless the hours contemplated in the fringe benefit are specified in the determination, a standard 8-hour day and 40-hour week is considered applicable. The total annual cost so determined is divided by 2,080, the standard number of non-overtime hours in a year of work, to arrive at the hourly cash equivalent. This principle may be illustrated by the following examples: