Joel Kotkin has an insightful blog entry over at Forbes.com (7/20/2011) discussing the demographics of urban living and migration in U.S. metropolitan areas. Citing numbers crunched by Wendell Cox, Kotkin notes that while Americans in their early and mid-twenties settle disproportionately in urban centers--much as planners have noted--census data from 2010 show that they move to the suburbs when they become thirtysomethings. As Joel writes:
"Some demographers claim that “white flight” from the city is declining, replaced by a “bright flight” to the urban core from the suburbs. “Suburbs lose young whites to cities,” crowed one Associated Press headline last year.
"Yet evidence from the last Census show the opposite: a marked acceleration of movement not into cities but toward suburban and exurban locations. The simple, usually inexorable effects of maturation may be one reason for this surprising result. Simply put, when 20-somethings get older, they do things like marry, start businesses, settle down and maybe start having kids.
"An analysis of the past decade’s Census data by demographer Wendell Cox shows this. Cox looked at where 25- to 34-year-olds were living in 2000 and compared this to where they were living by 2010, now aged 35 to 44. The results were surprising: In the past 10 years, this cohort’s presence grew 12% in suburban areas while dropping 22.7% in the core cities. Overall, this demographic expanded by roughly 1. 8 million in the suburbs while losing 1.3 million in the core cities."
And it's not just the traditional laggards that are experiencing this decline. Joel continues:
"More intriguing, and perhaps counter-intuitive, “hip and cool” core cities like San Francisco, New York and Boston have also suffered double-digit percent losses among this generation. New York City, for example, saw its 25 to 34 population of 2000 drop by over 15% — a net loss of over 200,000 people — a decade later. San Francisco and Oakland, the core cities of the Bay Area, lost more than 20% of this cohort over the decade, and the city of Boston lost nearly 40%."
The point, of course, is not that traditional central city cores are not benefiting from the in-migration of younger people. They are. Rather, the real question is whether this is a stable cohort for planning and urban development. If not, policies focusing on twentysomethings is not a sustainable approach to urban development or neighborhood revitalization.
For more on how demographic shifts are shaping America, pick up a copy of Joel's most recent book The Next Hundred Million: America in 2050.