For an annuity contract that provides for the payment of a single consideration, the minimum nonforfeiture amount is computed in the same manner as the minimum nonforfeiture amount for a contract with flexible considerations, except that:
(1) the net consideration amount to be used to compute the minimum nonforfeiture amount is the amount of the gross considerations paid under the contract less a contract charge of $75; and
(2) the percentage of the net consideration amount to be used to compute the minimum nonforfeiture amount is 90 percent.