The National Park Service Organic Act of 1916 established the Park Service within the Department of the Interior to promote and regulate the use of the National Park System with the purpose of conserving the scenery, natural and historic objects, and wildlife therein and to leave them unimpaired for the enjoyment of future generations. The Park Service manages its responsibilities through its headquarters office located in Washington, D.C., seven regional offices, and 409 individual park units that are part of the system. Park unit types include national parks, such as Yellowstone and Great Smoky Mountains; national historic parks, such as Valley Forge and the Chesapeake and Ohio Canal; national battlefields, such as Antietam and Fort Necessity; national historic sites, such as Ford’s Theatre and Theodore Roosevelt’s birthplace; national monuments, such as Muir Woods and the Statue of Liberty; national preserves, such as the Yukon-Charley Rivers and Big Cypress; national recreation areas, such as Lake Mead and the Chattahoochee River, and national lakeshores, such as Sleeping Bear Dunes and the Apostle Islands. Funding for the Park Service is composed of two sources: (1) annual appropriations and (2) fees, donations, and other funding sources. Annual appropriations. The Park Service generally receives funding through annual appropriations acts, which provide funds used by park units or applicable entities, such as states and local governments, in the following five accounts: Operation of the National Park System. Provides base funding for the operation of park units and for Park Service-wide programs. This funding is used by park units for visitor services, park protection, and maintenance projects, among other things. National Recreation and Preservation. Supports programs that assist state, local, and tribal governments, and private organizations with outdoor recreation, preservation, and environmental compliance. Historic Preservation Fund. Provides grants to state, territorial, and tribal governments and certain private groups for preserving historical and cultural resources. Construction. Supports planning and implementation of major rehabilitation and replacement projects at park units, along with unplanned, emergency construction projects. Land Acquisition and State Assistance. Uses funding from the Land and Water Conservation Fund to support Park Service land acquisition activities and provide grants to state and local governments for the purchase of land for recreation activities. Fees, donations, and other funding sources. The Park Service collects and uses funds from fees, donations, and other funding sources. These include: Entrance fees and amenity fees. The Federal Lands Recreation Enhancement Act (FLREA) authorizes the Park Service to collect and use recreation fees, including entrance fees and amenity fees for certain equipment and services, such as campgrounds. Franchise fees and commercial use authorization fees. The National Park Service Concessions Management Improvement Act of 1998 (Concessions Act) authorizes the Park Service to collect and use certain fees from concessioners that operate businesses in park units. Specifically, the Park Service may collect and use franchise fees from concessioners who operate restaurants, lodges, and other business operations inside park units. These fees are generally assessed as a percentage of the concessioners’ total gross receipts. The Park Service also collects fees for commercial use authorizations, which include small-scale commercial activities, such as leading workshops or tours. Rents. The Park Service is authorized to collect and use certain rents. Through its leasing program, the Park Service leases buildings and associated property to businesses, individuals, and government entities. Donations. The Park Service is authorized by law to receive and use cash donations and in-kind donations from individuals, nonprofit organizations, and corporations. Examples of in-kind donations include artifacts or services provided by nonprofit partner groups on behalf of the Park Service. The Park Service is also authorized to develop agreements with nonprofit partner groups, known as friends groups and cooperating associations. In general, friends groups engage in fundraising efforts on behalf of individual parks units, while cooperating associations provide interpretive services for visitors and manage retail operations at parks and share a portion of their proceeds from these operations with park units. The Park Service also has a volunteer program authorized by the Volunteers in the Parks Act of 1969. Volunteers help with a variety of tasks at park units, including doing maintenance work and providing interpretive services to visitors. Other funding sources. Other funding sources include transportation fees the Park Service collects to operate public transportation systems in park units; rents collected for employee housing; and funding from the U.S. Department of the Treasury for certain pension payments for United States Park Police annuitants. According to our analysis of OMB MAX data, total funding for the Park Service increased in nominal dollars from $2.7 billion in fiscal year 2005 to $3.1 billion in fiscal year 2014 (15 percent), as shown in table 1. However, when adjusted for inflation, total funding for the Park Service declined by 3 percent during this period. For fiscal years 2005 through 2014, the largest component of funding for the Park Service was its annual appropriations, which comprised 88 percent of its total funding on average, with fees, donations, and other funding sources comprising the remaining 12 percent. Over time, there has been some growth in the proportion of total Park Service funding that fees, donations, and other funding sources comprise (see fig. 1). Annual appropriations increased by 9 percent overall from fiscal year 2005 through fiscal year 2014 in nominal terms but declined by 8 percent after adjusting for inflation (see fig. 2). A large increase in appropriations came in fiscal year 2009, when the American Recovery and Reinvestment Act provided an additional $750 million to the Park Service. Since fiscal year 2010, annual appropriations for the Park Service have generally declined. Park Service officials told us that flat or declining appropriations have made it difficult to cover increases in salary and expenses for agency employees and to address the agency’s growing maintenance backlog. In addition, the number of park units in the system has been growing, and some Park Service officials said that this increase in units meant that the agency’s appropriations had to be divided among an increasing number of units. In 2006, there were 390 park units, and there are 409 park units as of November 2015. Fees, donations, and other funding sources grew 64 percent in nominal terms from fiscal year 2005 through fiscal year 2014 and have increased in most years, as shown in figure 3. Even after adjusting for inflation, funding from these sources increased by 39 percent during this period. Recreation fees, commercial service fees, and cash donations comprised on average 74 percent of the total fees, donations, and other funding sources for the Park Service for fiscal years 2005 through 2014. Park Service officials told us that these three revenue sources provided important support to park units. For example, from 2005 through 2011, recreation fees funded an estimated 8,575 projects at park units, including maintenance and other projects that enhanced the visitor experience, according to a 2012 report on the implementation of FLREA. In addition, during that time period, the Park Service used revenue from franchise fees to reimburse numerous concessioners that improved facilities in park units. Further, philanthropic donations enabled some parks to complete projects, such as improving trails or rehabilitating visitor centers. Some Park Service officials voiced concern to us that fees and donations could be viewed as a substitute for annual appropriations. They said that these sources are to be viewed as a supplement to annual appropriations but not a replacement. Revenues from recreation and commercial service fees and donations from philanthropic sources grew from fiscal year 2005 through fiscal year 2014. Specifically, revenues from recreation fees increased 26 percent during the period, while revenue from commercial service fees nearly tripled. Meanwhile, cash donations from philanthropic sources have fluctuated, while volunteer support has consistently increased. According to our analysis of Park Service data, revenues from recreation fees increased from about $148 million to about $186 million (26 percent) during the period we examined, as shown in figure 4. With the exception of fiscal years 2009, 2010, and 2013, revenues from recreation fees increased over the prior year. Revenues from recreation fees are comprised largely of entrance fees and amenity fees for equipment, services, and facilities, such as campsites. Revenues from entrance fees have been higher than amenity fees from fiscal year 2005 through fiscal year 2014, accounting for about 77 percent on average of the total recreation fees collected, with amenity fees on average accounting for the remaining 23 percent. Although recreation fee revenues have been generally increasing, the number of park units collecting entrance fees has declined from fiscal year 2008, the first year for which data are available according to Park Service officials, through fiscal year 2015. The number of park units charging amenity fees has remained largely constant over this period (see table 2). The decision to charge recreation fees involves individual park units, which make proposals to charge fees, and regional and headquarters officials who approve these fees. According to Park Service guidance, one of the guiding principles of the program is that parks will not collect recreation fees if the cost of collection exceeds the amount of revenue generated. For example, some park units do not have many visitors, so the administrative costs of charging these fees, which include paying staff to collect them, purchasing cash registers to process them, and hiring an armored car service to deposit them, can outweigh the anticipated revenues. Even with the decline in the number of parks collecting recreation fees, revenues grew over the period we examined, largely because the fees collected at a small number of parks account for a large portion of the fees collected. In fiscal year 2014, five national parks—Grand Canyon, Yosemite, Yellowstone, Rocky Mountain, and Zion—accounted for $59.6 million or about one-third of the total recreation fees collected that year. In addition, according to our analysis of the Park Service data, the top 50 park units collected about 88 percent of the total recreation fees collected in fiscal year 2014.