The spouse tier II benefit is computed as follows:
Example: An employee's tier II rate is $329.63 effective October 17, 1981. The spouse rate is $148.33 (45 percent * $329.63) effective October 17, 1981. This is increased to $151.89 effective June 1, 1982, by a cost-of-living increase of 2.4 percent. The spouse is 35 months under age 65, the present retirement age, when the annuity begins. The $151.89 rate is multiplied by 35/144 to produce an age reduction of $36.92. This is subtracted from $151.89 to produce a final rate of $114.97.
20 C.F.R. §226.32