Cities have been pivotal role to improved living standards, because of the opportunities they facilitate. This is particularly evident over the past two centuries, as world urbanization has risen from 3 percent to over 50 percent, and to more than 80 percent in the United States.
Many American cities, described commonly as urban cores, are functionally more suburban and exurban, based on urban form, density, and travel behavior characteristics. Data from the 2010 census shows that 42.3 percent of the population of the historical core municipalities was functionally urban core (Figure 1). By comparison, 56.3 of the population lived in functional suburbs and another 1.3 percent in functionally exurban areas (generally outside the urban areas). Urban cores are defined as areas that have high population densities (7,500 or per square mile or 2,900 per square kilometer or more) and high transit, walking and cycling work trip market shares (20 percent or more). Urban cores also include non-exurban sectors with median house construction dates of 1945 or before. All of these areas are defined at the zip code tabulation area (ZCTA) level, rather than by municipal jurisdiction. This is described in further detail in the “City Sector Model” note below.
Much attention has been given the increase in transit use in America. In context, the gains have been small, and very concentrated (see: No Fundamental Shift to Transit, Not Even a Shift). Much of the gain has been in the urban cores, which house only 14 percent of metropolitan area population. Virtually all of the urban core gain (99 percent) has been in the six metropolitan areas withtransit legacy cities (New York, Chicago, Philadelphia, San Francisco, Boston, and Washington).
The fortunes of U.S. core cities (municipalities) have varied greatly in the period of automobile domination that accelerated strongly at the end of World War II. This is illustrated by examining trends between the three categories of “historical core municipalities” (Figure 1). Since that time, nearly all metropolitan area (the functional or economic definition of the city) growth has been suburban, outside core municipality limits, or in the outer rings of existing, core municipalities.
Philadelphia was America’s first large city and served as the nation’s capital for all but nine months between the inauguration of George Washington is the first president in 1789 and the capital transferred to Washington, DC in 1800. Before the early 1900s, the United States Census Bureau had not developed a metropolitan area (labor market area) concept. However, the website peakbagger.com has attempted to define earlier metropolitan areas based on concepts similar to those used today. In the case of Philadelphia, this is important, because it was somewhat unique in having virtually adjacent, highly populated suburbs that make comparisons of municipal populations (the only population data available) misleading.
The 2013 annual metropolitan area population estimates by the US Census Bureau indicate a continuing and persistent dominance of population growth and domestic migration by the South. Between 2010 and 2013, 51 percent of the population increase in the 52 major metropolitan areas (over 1 million population) was in the South. The West accounted for 30 percent of the increase, followed by the Northeast at 11 percent and eight percent in the North Central (Midwest).
The term “Greater New York” was applied, unofficially, to the 1898 consolidation that produced the present city of New York, which brought together the present five boroughs (counties). When consolidated, much of the city of New York was agricultural. As time went on, the term “Greater” came to apply to virtually any large city and its environs, not just New York. By 2010, Greater New York had expanded to somewhere between 19 million and 23 million residents, depending on the definition.