Effects of per-vehicle entrance fees on U.S. National Park visitation rates

This study tested the hypothesis that increases in per-vehicle entrance fees at United States National Parks between the years 1996 and 2006 resulted in reduced numbers of park visitors. Analysis proceeded in three stages: (1) annual visitor numbers and entrance fees were plotted together over the 11 year period; (2) a difference-in-difference analysis was performed, comparing visitor trends for clusters of similar parks from the year before to the year after that in which fees were increased; and (3) the natural log of yearly visitor count was regressed on the natural log of fees in an attempt to quantify the elasticity relationship between the two variables. The analysis did not find a clear relationship between per-vehicle entrance fees and visitation rates. However, the possibility remains that such a relationship exists, at least for some parks