Thomas B. Edsall writes,
According to Romem, between 2005 and 2016, those moving into the San Francisco area had median household incomes averaging $12,639 a year more than the households of the families moving out, $70,015 to $57,376.
Conversely, in the struggling Syracuse metropolitan area (Clinton 53.9 percent, Trump 40.1 percent), families moving in between 2005 and 2016 had median household incomes of $35,219 — $7,229 less than the median income of the families moving out of the region, $42,448.
It’s a long essay, worth reading in its entirety. Edsall’s focus is on the evolution of the political coalition that makes up the Democratic Party. But I find the economic phenomenon interesting. The data support the Handle Hypothesis that urbanization has become a winners-take-most game. The article by Issi Romem that Edsall refers to is also worth reading. Romem writes,
Why do the expensive coastal metros exhibit positive income sorting? These metros are expensive because they have restricted their supply of new housing even as they continue to generate strong demand for it.
Kevin Erdmann and many others have been saying this for quite some time.
Related: Pew reports,
In 2001, 13 percentage points separated the shares of white and African-American renter households that were burdened: 26 and 39 percent, respectively. . .By 2015, the share of African-American-led renter households that were burdened had risen to 46 percent
Rent-burdened is defined as spending more than 30 percent of a household’s income on rent. Pointer from Tyler Cowen.
I think that the political threat to the Democratic Party is minimal. Group identity seems to overcome anything. The Democrats can be anti-Israel and still get most of the Jewish vote. Their policies make housing less affordable and drive African-Americans out of Washington, D.C. or San Francisco, but they still get most of the black vote.