Greater Houston, designated by the United States Office of Management and Budget as Houston–The Woodlands–Sugar Land, is the fifth-most populous metropolitan statistical area in the United States, encompassing nine counties along the Gulf Coast in Southeast Texas. With a population of 6,997,384 people as of 2018 census estimates and over 7 million in 2019, Greater Houston is the second-most populous in Texas after the Dallas–Fort Worth metroplex. The approximately 10,000-square-mile (26,000 km2) region centers on Harris County, the third-most populous county in the U.S., which contains the city of Houston—the largest economic and cultural center of the South—with a population of more than 2.3 million. Greater Houston is part of the Texas Triangle megaregion along with the Dallas–Fort Worth Metroplex, Greater Austin, and Greater San Antonio. Greater Houston also serves as a major anchor and economic hub for the Gulf Coast. Its Port of Houston is the second largest port in the United States, sixteenth largest in the world, and leads the nation in international trade.Greater Houston has historically been among the fastest-growing metropolitan areas in the United States; it was the fastest-growing in absolute terms during the 2013–2014 census year, adding 156,371 people. The area grew 25.2% between 1990 and 2000—adding more than 950,000 people—while the country's population increased only 13.2% over the same period, and from 2000 to 2007 alone, the area added over 910,000 people. The Greater Houston Partnership projected the metropolitan area would add between 4.1 and 8.3 million new residents between 2010 and 2050.Greater Houston has the seventh-highest metropolitan-area gross domestic product in the United States, valued at $490 billion in 2017. A major trade center anchored by the Port of Houston, Houston–The Woodlands–Sugar Land has the highest trade export value of all metropolitan areas, at over $120 billion in 2018, accounting for 42% of the total exports of Texas. As of 2020, Greater Houston is home to the headquarters of 22 Fortune 500 companies, ranking fourth among all metropolitan statistical areas.