There is created the education trust fund of 1992. The commissioner of finance and administration is authorized and directed to deposit into this fund all revenues earmarked and allocated specifically and exclusively for educational purposes under this part, §§57-4-306,67-4-1025,67-6-103, and any other statute providing for the collection of state taxes allocated for educational purposes. All expenditures from this fund shall only be made upon appropriations for educational purposes duly enacted by the general assembly. Educational purposes shall include, but not be limited to, payment of principal and interest on general obligation bonds authorized to fund capital projects for institutions of higher education. Any unencumbered funds and any unexpended balances of the fund remaining at the end of any fiscal year shall not revert to the general fund of the state, but shall be carried forward until expended for educational purposes pursuant to appropriations duly enacted by the general assembly.