Passage: Before becoming a territory, various indigenous peoples and Native Americans inhabited Indiana for thousands of years. Since its founding as a territory, settlement patterns in Indiana have reflected regional cultural segmentation present in the Eastern United States; the state's northernmost tier was settled primarily by people from New England and New York, Central Indiana by migrants from the Mid-Atlantic states and from adjacent Ohio, and Southern Indiana by settlers from the Southern states, particularly Kentucky and Tennessee.Indiana has a diverse economy with a gross state product of $359.12 billion in 2017. Indiana has several metropolitan areas with populations greater than 100,000 and a number of smaller industrial cities and towns. Indiana is home to professional sports teams, including the NFL's Indianapolis Colts and the NBA's Indiana Pacers, and hosts several notable athletic events, such as the Indianapolis 500 and Brickyard 400 motorsports races.

Question: What is the estimate population of Indiana's metropolitan areas?
100,000