Seventy-five percent of the revenues from the road use fee assessed pursuant to § 12-37-2850, and the one-time fee assessed pursuant to § 12-37-2860 must be distributed by the State Treasurer as provided in § 12-37-2870. Distributions must be made by the last day of the next month succeeding the month in which the fee is paid. The remaining twenty-five percent must be credited to the Infrastructure Maintenance Trust Fund to be used to finance expansion and improvements to existing mainline interstates.