This article from New Geography explains the trend away from urban areas to the suburbs.
The new 2017 US Census Bureau metropolitan area population estimates have been published. They show a significant increase in domestic migration away from the largest cities (the major metropolitan areas, with more than 1,000,000 population) toward the metropolitan areas with from 500,000 to 1,000,000 population. The data also shows an acceleration of suburban versus core county population growth within the major metropolitan areas themselves. The data is summarized in the table at the bottom of the article.
Stronger Net Domestic Migration in Metropolitan Areas under 1,000,000 Population
Earlier in the decade, the 53 major metropolitan areas (over 1,000,000 population) had greater net domestic migration than in the 54 middle-sized metropolitan areas (between 500,000 and 1,000,000 population). In fact, since 2012, net domestic migration in the major metropolitan areas have dropped every year. By 2016, the major metropolitan areas had a net domestic migration loss of 67,000, which accelerated to 166,000 in 2017. In contrast, the middle-sized metropolitan areas have experienced annual increases in net domestic migration each year since 2012. In 2017, the metropolitan areas with between 500,000 and 1,000,000 population gained 271,000 more net domestic migrants than the metropolitan areas with more than 1,000,000 population (Figure 1, see Note).
A more detailed analysis shows that metropolitan areas between 1.0 and 2.5 million population gained the most domestic migrants relative to their 2016 population (0.33 percent). The under 1,000,000 category (the “larger” metropolitan areas) have the second greatest net domestic migration (0.27%), while the 2,500,000 to 5,000,000 category shows a smaller increase (0.14 percent). Metropolitan areas between 5,000,000 and 10,000,000 had a small loss (minus 0.19 percent), while New York and Los Angeles, the two megacities (over 10,000,000), had an enormous 0.95 percent net domestic migration loss, at 209,000. (Figures 2 and 3).
Domestic Migration to Suburbs Accelerates
Domestic migration also continues to accelerate to the suburbs of the major metropolitan areas. The core counties of the 50 major metropolitan areas (over 1,000,000) with more than one county have continued to shed domestic migrants (Note). Between 2016 and 2017, nearly 438,000 net residents moved from the core counties (which include the urban cores) to elsewhere in the nation. The suburban counties of the same metropolitan areas gained 252,000. Thus, the domestic migration gain in the suburbs was 690,000 more than in the core counties. (Figure 4).
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