America’s national parks are a major economic engine. In 2024, outdoor recreation made up 2.4 percent of U.S. GDP, according to Bureau of Economic Analysis data, as Americans flocked to trails, waterways, and campsites in record numbers. National parks alone saw their highest visitation ever—generating $56 billion in total economic output.
Yet, even as demand surged, federal support declined. Budget and staffing cuts reduced funding for key agencies, including the National Park Service (NPS), the Bureau of Land Management, and the Forest Service. By the end of 2025, the NPS had lost nearly a quarter of its permanent workforce to buyouts, forced resignations, and a prolonged hiring freeze.
Linda J. Bilmes ’80, M.B.A. ’84, Moynihan senior lecturer and public policy expert at Harvard Kennedy School, has spent years studying the economics of public investment. A former chief financial officer of the U.S. Department of Commerce under President Bill Clinton and co-author of Valuing the U.S. National Parks: America’s Best Investment (2019), she studies how government spending shapes long-term economic outcomes.
In this interview, edited for length and clarity, Bilmes discusses the economic contributions, and future, of the U.S. National Park System.
1) Why do we struggle to measure, and defend, the government’s investment in public lands?
It’s difficult to fully account for the value of national parks using traditional accounting measures, or to translate it into the national budget. The entire National Park Service budget is less than $5 billion—a tiny fraction of the total estimated value.
The public recognizes that the 400 national park holdings—including national parks, seashores, monuments, and historical places—have an intrinsic worth. My research with co-author John Loomis found that Americans would pay $92 billion in higher taxes simply not to lose these special places and their core programs (such as protecting landscapes and historical landmarks).
2) You’ve called national parks “America’s best investment.” How do they contribute to the economy?
In addition to the economic value, we identified billions of dollars that the national parks help to generate for the economy. These include serving as pristine locations for blockbuster movies (including Star Wars, E.T., Planet of the Apes, and dozens more), producing educational curriculum for schools, and promoting tourism, which helps local economies.
The NPS also safeguards botanical species, wildlife, and cultural treasures, and it has a mission to protect these lands and places forever. It’s hard to put a number on how great an investment this is.
3) How do you calculate the economic value of the parks’ environmental contributions?
That’s a great question that is broader than the National Parks. For example, John Loomis and I, working with Harvard Kennedy School student Adam Banasiak, found that the NPS sequesters nearly $1 billion in carbon and helps maintain watersheds which supply fresh drinking water to millions of Americans.
But these benefits don’t show up as assets on the U.S. balance sheet. In many countries, including the U.K., South Africa, and New Zealand, there are serious efforts to assign a monetary value to “natural capital.” Economists and statisticians have developed robust methods of valuing these assets. For example: we can compare the cost of preserving forests, which provide natural filtration systems for drinking water, to building a filtration plan (which costs $10 billion plus operating costs).
4) What have been the most significant recent policy shifts affecting America’s national parks?
I’ll start with the good news: The U.S. added more than 265 acres of public lands and waters in national monuments by the end the Obama administration, created several new NPS units, and celebrated [the NPS] centennial in 2016. This drew millions of visitors into the parks, and the National Park Foundation raised nearly $500 million in private donations, far outpacing its goals.
Then in 2020, during his first administration, President Trump signed the Great American Outdoors Act, the biggest land conservation legislation in a generation. It strengthened the Land and Water Conservation Act—guaranteeing $900 million per year in perpetuity to acquire land for recreation and conservation—and established a fund to fix deferred maintenance at national parks, wildlife refuges, and forests.
But in 2025, the DOGE process hit the NPS badly. The agency lost about one quarter of its staff, including rangers, scientists, and technical experts. The Trump administration’s 2027 budget calls for a further 25percent cut to NPS operations, which would eliminate thousands more positions and drastically cut the park construction maintenance budget, even as parks face a large backlog of repairs. This would be disastrous for the NPS, its programs, and the millions of people who visit.
5) What’s the long-term economic outlook for the National Parks?
I had the privilege of serving on the National Park System Advisory Board and the National Parks Second Century Commission, which focused on how to protect the parks over the next 100 years. We quickly realized that the mission of the National Park Service was an poorly aligned with its funding structure, which was an annual operational budget.
We helped persuade Congress to establish an endowment for the National Parks and to restructure the National Park Foundation so it could effectively solicit and manage large private donations and grow that endowment. These recommendations have now been implemented. Public support for the parks remains strong and bipartisan, which gives me confidence that over the long-term, the NPS will be sustained; and its mission will be fulfilled for future generations.
