China the largest trade-partner of US

China for the first time has replaced Canada and becomes the largest partner of the US.Reason for decline of Canada's exports:Crude oil is among main exports of Canada and due to a slump in oil prices which in turn reduced the value of Canadian exports.
China's export to US: mainly comprise of computer products, toys, home appliances, footwear, audio visual equipment, electronic components and plastic products. 
US exports to China: soybeans, aircraft, autos, waste and scrap, semiconductors, measuring instruments, communication equipment and meat and poultry.