The
United States is the world's largest national economy, representing 22% of
nominal global GDP and 17% of
global GDP (PPP). The United States' GDP was estimated to be $17.914 trillion as of Q2 2015. The
U.S. dollar is the
currency most used in
international transactions and is the world's foremost
reserve currency. Several countries
use it as their official currency, and in many others it is the
de facto currency. The United States has a
mixed economy and has maintained a stable overall GDP growth rate, a moderate unemployment rate, and high levels of research and capital
investment. Its seven
largest trading partners are
Canada,
China,
Mexico,
Japan,
Germany,
South Korea, and the
United Kingdom.