The constitution sets aside money to build up the body of these funds from the proceeds of mineral, oil and gas leases and royalties from state lands. Revenue from those funds is used to purchase financial securities that provide the state with revenue from investment returns. These are made by the Bureau of Investments in the state’s Department of Treasury. The Natural Resource Trust Fund’s investment portfolio, for instance, is composed of roughly 35% in bonds and 65% in public and private equities, with the 10-year return projected to be 5.5%. Investment returns finance the annual spending programs allowed through the funds.
Not all annual revenue generated by state leases and royalties builds equity in these funds. Some is allocated directly for programs allowed through these funds. Constitutional language prohibits the state from spending more than half of the annual revenue to the SPEF directly on programs, however.
The NRTF has a board of trustees that, with recommendations from the treasury department, determines how much to spend each year. The board also decides which projects to fund. Last December, the trust fund board approved $25.6 million in acquisition and development grants. Projects can take years to complete after they are approved, and in fiscal year 2019, the NRTF took in $45 million in revenue from investments while making $53 million in expenditures.
The State Parks Endowment Fund does not have a board of trustees. Instead, annual allotments are determined by the Legislature and put into its annual state budgets. For fiscal year 2020, the state appropriated $24.2 million from the SPEF. Of that amount, $7 million went to repair and maintenance of state parks, $11.4 million went to state parks operations, $2.8 million went into state forest management, and the rest went to support administration costs.
 Gregory J. Parker, “Michigan Public School Employees’ Retirement System Retirement Plan Review” (Michigan Department of Treasury, Bureau of Investments, Mar. 21, 2013), 6, https://perma.cc/ANX4-9YVZ.
 Author correspondence with Ron Leix, deputy public information officer of the Michigan Department of Treasury, Sept. 9, 2020.
 Mich Const art. IX § 35a.
 “Michigan Natural Resources Trust Fund Board of Trustees Meeting Minutes of December 11, 2019” (Michigan Department of Natural Resources, March 3, 2020), https://perma.cc/BJ4R-CMVF.
 “State of Michigan: Comprehensive Annual Financial Report” (State of Michigan, March 6, 2020), 233, https://perma.cc/7X73-J4JS.
 “Michigan Public Act 166 of 2020” (State of Michigan, Sept. 30, 2020), 252–258, https://perma.cc/KE99-8NHW.