In the United States, a metropolitan area is officially called a Metropolitan Statistical Area. Two or more adjacent metropolitan statistical areas form a Consolidated Metropolitan Statistical Area. U.S.
metropolitan areas have at least one city or urban area with a population of 50,000 or more, and include the entire county in which the city is located. Adjacent counties may be considered part of
the area, depending on their population density and the number of workers who commute to jobs in
the central county. The term greater applied to a city refers to a metropolitan area, such as Greater
Paris. In England, clusters of small cities around a large city are called metropolitan counties.
In developed countries, most people live in metropolitan areas. In the United States, about 80 percent of the people live in the nation's 268 metropolitan statistical areas. In Canada, about 60 percent of the people reside in 25 metropolitan areas.
The development of suburbs
As cities grow, people move beyond official city boundaries, creating suburbs. This process of suburbanization has been going on since the late 1800's. Several factors contributed to the development of metropolitan areas. Originally, large numbers of people came from rural areas to
central cities in search of employment. This population shift produced overcrowded cities, causing other people to move to outlying areas. The use of automobiles, together with the improvement of
roads and highways, increased tremendously following the end of World War II in 1945. As a result, more and more people have settled in communities outside of central cities since the late 1940's.
By 1970, more people in U.S. metropolitan areas lived in suburbs than in central cities. But by the early 1980's, the rate of suburban growth had decreased for a number of reasons. For example,
many people moved to the suburbs to avoid such problems of big cities as crime, housing shortages, and racial conflicts. However, as the suburbs grew larger, they developed the same problems.
Urban revitalization programs drew some people back to central cities.
People who live in the suburbs of a central city have traditionally considered the city as their workplace because of its commercial and industrial activities. Suburbanites also use the city's cultural, professional, and recreational facilities and services. Since the 1950's, however, many businesses and industries have moved to the suburbs. Today, many suburbanites who once
commuted to and from work in the city work, shop, and enjoy various recreational activities in the suburbs.