2.Population Distribution

The United States is a highly urbanized country.As of 2011，about 250 million Americans live in or around urban areas.That means more than three-quarters of the US population shares just about three percent of the US land area.

The most densely populated region is the northeastern part of the country，which includes the states of New England，the Middle West and the Middle Atlantic.The region takes up about one quarter of the total land area of the country，but about half of the US total population is living here.This region has many great cities such as New York City，the home of the United Nations，is the largest city in the US with more than 21million people living in its five boroughs and surrounding suburbs.Chicago，the third largest city in the US，has a metropolitan area population of over 9million people.Since most of them live in the many metropolises，northern New England is still rather empty with wild picturesque scenery for tourists while the Midwest still has huge，sparsely populated open space for farming.The Northeast as a whole has had a low increase in population.

The Great Plains between the Mississippi and the Rocky Mountains are an area with a comparatively small population.Texas is the largest state in this region.It had a population of 25，145，561in 2010，exceeding New York and having become the second most populous state in the US.The northern part of the Great Plains is rather empty and featureless.In the combined area of North and South Dakotas，Nebraska and Kansas，an area as great as France and Italy put together，there were only 6，166，230inhabitants（2010）.

The South，including Virginia，North and South Carolinas，Georgia，Florida，Alabama，Mississippi，Tennessee，Kentucky，Louisiana，and Arkansas，had a population of almost 76.3million people in 2010.This number of population is not very large against the size of the South.There are also some big metropolitan areas in this region.Atlanta，for example，had a population of 4.1million people in 2000，and Miami，of over 3.87million people.The South used to be sparsely populated，but now many Americans are moving there.The South，at present，leads in numerical increase in population.

The West，including all the states west of the Rocky Mountains，is not densely populated，except for some metropolitan centers like Los Angles，and San Francisco.The population distribution in the West is quite uneven.Some states with very small areas may have a large population while others with large areas may have a small population.For example，the state of Washington with 176，000km² had a population of 6，724，540（2010），while Montana with 381，000km².only had 985，415people（2010）.California，the most populous state in the US，had a population of 37，253，956in 2010.Now the West has about 20%of the nation’s population.It leads in percentage increase in population.