From the testimony of Todd Hitt to U.S. House Committee on Small Business:

Writing in National Affairs in 2014, Eli Lehrer and Lori Sanders of the R Street Institute also tied geographic mobility with income inequality. Lehrer and Sanders said, “This decline in Americans’ geographic mobility has correlated with a well-documented 40-year trend of falling income mobility. While this correlation does not, by itself, prove a causal link, the evidence that geographic mobility can mitigate poverty is robust.