Around 1990, with the collapse of the Soviet Union, restrictions on private sales, including grain, ceased to be enforced. It is estimated that in the early 2000s, the average North Korean family drew some 80% of its income from small businesses that were technically illegal (though unenforced) in North Korea. In 2002, and in 2010, private markets were progressively legalized. As of 2013, urban and farmer markets were held every 10 days, and most urban residents lived within 2 km of a market.