This info is provided by the Food and Agricultural Organization of the United Nations.
"The 2011 FAO assessment of global food losses and waste (1) estimated that each year, one-third of all food produced in the world for human consumption never reached the consumer’s table. This not only means a missed opportunity for the economy and food security, but also a waste of all the natural resources used for growing, processing, packaging, transporting and marketing food.
Through an extensive literature search, the 2011 assessment of food wastage volumes gathered weight ratios of food losses and waste for different regions of the world, different commodity groups and different steps of the supply chain. These ratios were applied to regional food mass flows of FAO’s Food Balance Sheets for the year 2007."