I never said anything about percent of food, my comment was based on type of food. We have huge subsidies for some types of food. That does not mean ex: pot growers get a large subsidy. It's really a fairly narrow group of foods which get the vast majority of subsidies and are then produced in truly mind boggling quantities.
There was a great corn documentary a while ago where a small processor kept making larger larger grain silo's for a while as productivity increased. Until, they simply gave up they now just have a huge pile with a tarp over it. http://www.imdb.com/title/tt1112115/