Tenn. Code Ann. § 67-3-902: Investment of idle funds from 1986 gasoline tax increases

All funds from the increase in taxes imposed by chapter 931 of the Acts of 1986, and allocated to the state highway fund shall be placed in a separate account and, to the extent not required for the projects provided for in chapter 931 of the Acts of 1986, shall be invested pursuant to § 9-4-603 , with the investment income credited to the highway fund.