Iowa ( EYE-ə-wə, Lakota: Ayúȟwa) is a landlocked state in the upper Midwestern region of the United States. It borders the Mississippi River to the east and the Missouri River and Big Sioux River to the west; Wisconsin to the northeast, Illinois to the east and southeast, Missouri to the south, Nebraska to the west, South Dakota to the northwest, and Minnesota to the north. Iowa is the 26th largest in total area and the 31st most populous of the 50 U.S. states, with a population of 3,190,369, according to the 2020 census. The state's capital, most populous city, and largest metropolitan area fully located within the state is Des Moines. A portion of the larger Omaha, Nebraska, metropolitan area extends into three counties of southwest Iowa. Iowa has been listed as one of the safest U.S. states in which to live. During the 18th and early 19th centuries, Iowa was a part of French Louisiana and Spanish Louisiana; its state flag is patterned after the flag of France. After the Louisiana Purchase, people laid the foundation for an agriculture-based economy in the heart of the Corn Belt. In the latter half of the 20th century, Iowa's agricultural economy began to transition to a diversified economy of advanced manufacturing, processing, financial services, information technology, biotechnology, and green energy production. As of 2018, 22.6 million hogs outnumbered Iowans by more than 7 to 1 in 8,000 facilities large enough to require manure management plans.