As this month’s cover story relates, private businesses operating in public parks can take away much-needed revenue from parks’ operating budgets. But how much do parks really cost? A report by Resources for the Future shows the breakdown of costs.

14 million: Number of acres of state parkland in the United States.

720 million: Number of visitors to state parks each year.

$14 billion: Conservative estimate of the social benefits of recreation that state parks provide per year.

$2.3 billion: Annual costs of operating America’s state parks.

$31 million: Average cost per state for the state parks budget.

$3.25: Average cost per visit across all state parks in the United States.

39: Average percentage of total state park operating costs covered by park-generated revenues in FY 2011.

20: Average percentage of total state park operating costs covered by dedicated revenues in FY 2011.

34: Average percentage of total state park operating costs covered by general-fund revenues in FY 2011.

59: Average percentage of total state park operating costs covered by general-fund revenues in FY 1990.

.001 to .00375: Sales tax percentage dedicated to state parks in Arkansas, Minnesota, and Missouri (averaging $20 to $30 per person annually).

$6: Annual fee per vehicle for a state park entrance pass in Montana.

$30: Annual fee for two vehicles for a state park “Discover” pass in Washington State.

27.3: Percentage of vehicle owners in Michigan who purchased a “Recreation Passport” state parks entrance pass ($10 per vehicle).

Source: Paying for State Parks, Evaluating Alternative Approaches for the 21st Century by Resources for the Future.