Sec. 8.03. CREDITS TO MEMBER'S DROP ACCOUNT. Each month after a member makes an election to participate in the DROP and until the member's retirement, the board of trustees shall cause an amount equal to the retirement annuity that the member would have received under Section 5.04 of this Act for that month if the member had left active service and been granted a retirement annuity on the effective date of the election under Section 8.02 of this Act to be credited to a separate DROP account maintained within the fund for the benefit of the member. The member's contributions under Section 10.01(d) of this Act made after the effective date of the election to participate in the DROP shall also be credited to the member's DROP account. Amounts held in a member's DROP account shall be credited at the end of each calendar month with interest at a rate equal to one-twelfth of five percent until the member's retirement.