who has the second largest economy in the world
List of countries by GDP (nominal) Although the rankings of national economies have changed considerably over time, the United States has maintained its top position since the Gilded Age, a time period in which its economy saw rapid expansion, surpassing the British Empire and Qing dynasty in aggregate output.[13][14] Since China's transition to a market-based economy through privatisation and deregulation,[15][16] the country has seen its ranking increase from ninth in 1978 to second to only the United States in 2016 as economic growth accelerated and its share of global nominal GDP surged from 2% in 1980 to 15% in 2016.[14][1] India has also experienced a similar economic boom since the implementation of economic liberalisation in the early 1990s.[17] When supranational entities are included, the European Union is the second largest economy in the world. It was the largest from 2004, when ten countries joined the union,[18] to 2014, after which it was surpassed by the United States.[19]
Economy of the United States The economy of the United States is a highly developed mixed economy.[29][30] It is the world's largest economy by nominal GDP and the second-largest by purchasing power parity (PPP).[31] It also has the world's seventh-highest per capita GDP (nominal) and the eleventh-highest per capita GDP (PPP) in 2016.[32][33] The US has a highly diversified, world-leading industrial sector.[34] It is also a high-technology innovator with the second-largest industrial output in the world.[34] The U.S. dollar is the currency most used in international transactions and is the world's foremost reserve currency, backed by its science and technology, its military, the full faith of the U.S. government to reimburse its debts, its central role in a range of international institutions since World War II, and the petrodollar system.[35][36] Several countries use it as their official currency, and in many others, it is the de facto currency.[37][38] Its largest trading partners are China, Canada, Mexico, Japan, Germany, South Korea, United Kingdom, France, India, and Taiwan.[39]