|New residential construction (in blue) in Philadelphia’s South Philadelphia neighborhood. Source: southphillyreview.com|
I think it is, and I think it’s quantifiable.
I started an analysis with a couple of simple premises. The first premise is that a simple definition of gentrification is that it represents the transition of a low-income neighborhood into a high-income neighborhood. The second premise is that, within metro areas, household incomes tend to be lower in central cities and higher in suburban areas. For analytical purposes, the thinking is that if we examine changes in household income over time, at both the city and metro area levels, we should be able to get an idea of cities where the influx of new residents and new money has had the greatest impact — where city household incomes are closing the gap with their respective metro areas.
I analyzed U.S. Census Bureau American Community Survey data between 2000 and 2015, looking at median household income figures for the 14 largest urbanized areas in America, and their respective central cities (that includes all U.S. urbanized areas with more than 3 million people). I calculated the ratio of each city’s median household income to the similar figure for the urbanized area, and charted changes between 2000-2010, 2010-2015, and 2000-2015.
Here’s what I found:
Here’s a table that illustrates those changes:
A few interesting observations emerge. Los Angeles and Miami both made median household income gains relative to their urbanized areas from 2000-10, but regressed from 2010-15. Philadelphia was late to join the group, showing a gap widening between 2000-10, but made gains over the next five years. As for Dallas, Houston, Detroit and Phoenix, none has yet to experience gentrification at levels that have impacted overall incomes. Three possible reasons stand out — 1) an abundance of available and affordable land at the metro edges that enables peripheral growth; 2) a possible lack of actual walkable urbanism within city limits (as cities that are more “suburban” in their development character, they may have less of the housing types and amenities driving gentrification activity in other cities); and 3) in Detroit’s case, a remaining reluctance among middle and upper-middle class residents to inhabit and invest in large numbers.
If you annualize the data, some other trends appear. When comparing the 2000-10 and 2010-15 periods, it appears the pace of income gap closure is accelerating in New York, DC, Boston, San Francisco and Seattle. Again, Philadelphia’s reversal over the last five years may mean it’s joining this group. Atlanta seems to cooled off significantly since the 2000-10 period, and Chicago has fallen back slightly from its modest 2000-10 gains. The recent regressions seen in Los Angeles and Miami mean they join the Dallas-Houston-Detroit-Phoenix group.
Please note that this is a measure of gentrification’s impact on a city, not a measure of the scale of gentrification taking place. There are some factors that, using this measure, can distort the gentrification impact. The factors can highlight a greater impact in some cities and a lesser one in others. For example, in New York, with more than 3 million households, it’s conceivable that maybe 200,000-300,000 higher income households contributed to closing city/suburban median household income gap. That requires a massive influx of people and investment in New York toward gentrification, at a scale unseen elsewhere in the nation. In the much smaller DC and Atlanta, with a total of about 300,000 and 200,000 households respectively, far smaller numbers of new higher income households can have a greater impact on these figures — the changes may even be more visible and happen more quickly.
Another way gentrification’s impact can be distorted? The size of the city relative to the entire metro area. Atlanta comprises less than ten percent of its region’s population; for DC, just thirteen percent. Small changes there, relative to the rest of their regions, can have a significant impact. However, in Phoenix or Houston, which each comprise nearly forty percent of their region’s population, making a dent might be far more difficult.
The data is out there for us to examine the impact of gentrification within cities, and evaluate how the gentrification process works differently in different metro areas. Look for more analysis in this vein in the coming days and weeks.