This means because of the protectionist nature of the CAP, agricultural products from developing countries are rendered incompetitive in both Europe (an important export market for developing countries) and on their home markets (as European agricultural products are dumped on developing countries' markets with help from European agricultural subsidies). This controversy surrounds every system of agricultural subsidies (the United States' policy of subsidizing farmers is also controversial). The CAP is also controversial because 40% of the EU's budget is spent on it, and because of the overproduction caused by it.