If a motor vehicle exceeding 14,000 pounds gross vehicle weight rating is registered for less than a 12-month registration period, the registration fees are:
(1) for not more than three months, 30% of the regular registration fee;
(2) for in excess of three months but not more than six months, 60% of the regular registration fee;
(3) for in excess of six months and not more than nine months, 90% of the regular registration fee; and
(4) for anything in excess of nine months but not more than 12 months, the entire registration fee.