The Ford Foundation, one of the first to use PRIs, began its program in 1968. According to a 1974 review of its first five years, even after accounting for loan losses, administrative costs, and the opportunity cost inherent in providing money at a below-market rate of interest, Ford found that “$1 million invested in a PRI is the equivalent of $5 million in grant expenditures.” Since then, the use of PRIs has grown steadily. In 2003, the top five PRI providers were the David & Lucile Packard Foundation, followed by Ford, the John D. and Catherine T. MacArthur Foundation, the F. B. Heron Foundation, and the Otto Bremer Foundation

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