Summary: NATO does not routinely evaluate members' cost shares for any of its three commonly funded budgets. Rather, NATO has adjusted the shares on the basis of comprehensive reviews occurring at no specific time intervals or in response to discrete events, such as the entry of a new member. Cost shares for the NATO Security Investment Program (NSIP) budget, which primarily funds infrastructure improvements, were most recently reviewed in 1990. They have been subject to comprehensive reviews more often than the civil budget or the military budget. NATO has adjusted cost share because of discrete events infrequently--in 1966, when France withdrew from NATO's military structure; in 1982, when Spain joined NATO; and in 1994, when Canada sought to decrease its NSIP share. NATO has used various methods to adjust cost shares. For example, in 1955, NATO used expenditures to comprehensively review and adjust shares for its civil and military budgets. In contrast, changes to NSIP cost shares in 1990 were based on negotiations among members that considered such factors as each nation's capacity to pay and the expected benefits from NSIP projects. NATO has also relied on negotiations to adjust cost shares in response to discrete events. In 1997, the United States' actual cost-share across all the common budgets was 28.45 percent.
