The major agricultural produce is rice which covers about 60% of the country's total cultivated land area. Rice accounts for 97% of total food grain production by weight. Through collaboration with the International Rice Research Institute (IRRI), 52 modern rice varieties were released in the country between 1966 and 1997, helping increase national rice production to 14 million tons in 1987 and to 19 million tons in 1996. By 1988, modern varieties were planted on half of the country's rice fields, including 98% of the irrigated areas. In 2011, Myanmar's total milled rice production accounted for 10.60 million tons, an increase from the 1.8 per cent back in 2010.