China,[h] officially the People's Republic of China (PRC),[i] is a country in East Asia. It is the second-most populous country after India, with a population exceeding 1.4 billion, representing 17% of the world's population. China borders fourteen countries by land[j] across an area of 9.6 million square kilometers (3,700,000 sq mi), making it the third-largest country by area.[k] The country is divided into 33 province-level divisions: 22 provinces,[l] 5 autonomous regions, 4 municipalities, and 2 semi-autonomous special administrative regions. Beijing is the capital, while Shanghai is the most populous city by urban area and largest financial center. China has the world's second-largest economy in terms of nominal GDP,[288] and the world's largest in terms of purchasing power parity (PPP).[289] As of 2022, China accounts for around 18% of the global economy by nominal GDP.[290] China is one of the world's fastest-growing major economies,[291] with its economic growth having been almost consistently above 5 percent since the introduction of the reform and opening up policy in 1978.[292] According to the World Bank, China's GDP grew from $150 billion in 1978 to $18.74 trillion by 2024.[293] It ranks 75th by nominal GDP per capita, making it an upper-middle income country.[294] Of the world's 500 largest companies, 135 are headquartered in China.[295]