During the 1960s Thailand experienced one of the most rapid growth rates among developing countries: more than 10% per year in GNP, and about 8% per year in real output. The First National Economic Development Plan (1961-1966) was successfully implemented. US grant economic assistance totalled about US$500 million through the end of 1970. Direct military assistance totalled another US$800 million for the same period, continuing at the rate of US$25–55 million per year. According to US government statistics, between 1950 and 1987 the US provided Thailand with more than US$2 billion in military assistance.