AMOUNT OF REFUND CREDIT FOR MONTHLY INSTALLMENT CONTRACT.

(a) This section:

(1) applies only to a refund credit on the prepayment of a retail installment contract that is payable in substantially equal successive monthly installments beginning one month after the date of the contract; and

(2) does not apply to a retail installment contract in which the time price differential is computed using the true daily earnings method or the scheduled installment earnings method.

(b) On a contract for a commercial vehicle other than a heavy commercial vehicle the minimum amount of the refund credit is computed by:

(1) subtracting an acquisition cost of $25 from the original time price differential; and

(2) multiplying the amount computed under Subdivision (1) by the percentage of refund computed under Subsection (d).

(c) On a contract for a heavy commercial vehicle the minimum amount of the refund credit is computed by:

(1) multiplying the amount of the original time price differential by the percentage of refund computed under Subsection (d); and

(2) subtracting an acquisition cost of $150 from the amount computed under Subdivision (1).

(d) The percentage of refund is computed by:

(1) computing the sum of all of the monthly balances under the contract's schedule of payments; and

(2) dividing the amount computed under Subdivision (1) into the sum of the unpaid monthly balances under the contract's schedule of payments beginning:

(A) on the first day, after the date of the prepayment or demand for payment in full, that is the date of a month that corresponds to the date of the month that the first installment is due under the contract; or

(B) if the prepayment or demand for payment in full is made before the first installment date under the contract, one month after the next monthly anniversary date of the contract occurring after the prepayment or demand.

(e) A refund credit is not required if the amount of the refund credit is less than $1.