The economy of the United States is the world's largest national economy and the world's second largest overall economy, the GDP of the EU being approximately $2 trillion larger. Its nominal GDP was estimated to be $15.8 trillion in 2012 , approximately a quarter of nominal global GDP. Its GDP at purchasing power parity is the largest in the world, approximately a fifth of global GDP at purchasing power parity. The U.S. is one of the world's wealthiest nations, with abundant natural resources, a well-developed infrastructure, and high productivity. It has the world's sixth-highest per capita GDP (PPP). The U.S. is the world's third-largest producer of oil and second-largest producer of natural gas. It is the second-largest trading nation in the world behind China. Its five largest trading partners are : European Union, Canada, China, Mexico and Japan.