This was the end of U.S. air support, the last American aircraft departing Cambodian airspace on 15 August. From the beginning of Operation "Breakfast" the U.S. Air Force had dropped 539,129 tons of ordnance on Cambodia, 257,465 tons of which had been dropped during the last six months of the operation. During 1974, Cambodia continued to collapse. More than half of the population had become refugees and malnutrition and disease stalked a nation that had once been the best fed in Southeast Asia.