Subsistence agriculture still accounts for half of the GDP and provides 80% of employment. Only 4% of the country is arable land and a mere 0.3% used as permanent crop land, the lowest percentage in the Greater Mekong Subregion. The irrigated areas under cultivation account for only 28% of the total area under cultivation which, in turn, represents only 12% of all of the agricultural land in 2012. Rice dominates agriculture, with about 80% of the arable land area used for growing rice. Approximately 77% of Lao farm households are self-sufficient in rice. Laos may have the greatest number of rice varieties in the Greater Mekong Subregion. The Lao government has been working with the International Rice Research Institute of the Philippines to collect seed samples of each of the thousands of rice varieties found in Laos.