The Conservation Reserve Program is the largest U.S. land retirement program. Under the CRP, landowners voluntarily retire environmentally sensitive cropland for 10 to 15 years in exchange for an annual rental payment. Once a CRP contract expires, land may be reenrolled. However, since 2008, the acreage enrollment cap has decreased, reducing opportunities for reenrollment—and almost 13 million acres have exited the program.