Dayton (pronounced /deɪtn/) is the 6th largest city in the U.S. state of Ohio and the county seat of Montgomery County, the fifth most populous county in the state. The population was 141,527 at the 2010 census. The Dayton Metropolitan Statistical Area had a population of 841,502 in the 2010 census. As of the 2010 census, Dayton is the fourth largest metropolitan area in Ohio and the 61st largest metropolitan area in the United States. The Dayton-Springfield-Greenville Combined Statistical Area had a population of 1,072,891 in 2010 and is the 43rd largest combined statistical area in the United States. Dayton is situated within the Miami Valley region of Ohio, just north of the Cincinnati metropolitan area.
Dayton is within 500 mi (805 km) of 60% of the population and manufacturing capacity of the U.S. and so is defined as one of only two major logistics centroids in the United States. It plays host to significant industrial, aerospace, and technological/engineering research activity and is known for the many technical innovations and inventions developed there. Much of this innovation is due in part to Wright-Patterson Air Force Base and its place within the community. With the decline of heavy manufacturing, Dayton's businesses have diversified into a service economy, including the insurance and legal sectors and most importantly the healthcare and government sectors.
Other than defense and aerospace, healthcare accounts for much of the Dayton area's economy. Hospitals in the Greater Dayton area have an estimated combined employment of nearly 32,000, a yearly economic impact of $6.8 billion. It is estimated that Premier Health Partners, a hospital network, contributes more than $2 billion a year to the region through operating, employment, and capital expenditures. In 2011, Dayton was rated the #3 city in the nation out of the top 50 cities in the United States by HealthGrades for excellence in health care. Many hospitals in the Dayton area are consistently ranked by Forbes, U.S. News & World Report, and HealthGrades for clinical excellence.