(D) If the absence or leave does not begin and end in the same year or the member does not purchase the credit under division (C) of this section, a member may purchase credit for the absence or leave by paying to the system the sum of the following for each year of credit purchased:

1. (1) An amount determined by multiplying the employee rate of contribution in effect at the time the absence or leave commenced by the member's annual compensation for the member's last full year of service prior to the commencement of the absence or leave, or, if the member has not had a full year of service, the compensation the member would have received for the year the absence or leave commenced had the member continued in service for a full year;
2. (2) Interest compounded annually, at a rate determined by the board, on the amount determined under division (D)(1) of this section from the day following the last day of the year in which the absence or leave terminated to the date of payment;
3. (3) Interest compounded annually, at a rate determined by the board, on an amount equal to the employer's contribution required by this division from the day following the last day of the year in which the absence or leave terminated to the date of payment. The employer shall pay to the system for each year of credit purchased under this division an amount determined by multiplying the employer contribution rate in effect at the time the absence or leave commenced by the member's annual compensation for the member's last full year of service prior to the commencement of the absence or leave, or, if the member has not had a full year of service, the compensation the member would have received for the year the absence or leave commenced had the member continued in service for a full year.