For purposes of determining the present value of an annuity, an interest for life or a term of years, or a remainder or a reversionary interest, the Treasury publishes a monthly Charitable Federal Midterm Rate as described under Code Section 7520. The taxpayer may elect to use the rate in effect for the month in which the transfer occurs or either of the two months preceding the transfer. The rate for the following month is published during the third week of each month.