Many Philadelphia millennials are faring worse than Gen Xers

Millennials born to low-income families in the Philadelphia region have lost the most economic ground compared to their Gen X predecessors among the largest U.S. metros, a new analysis finds.

Why it matters: Intergenerational mobility — the idea that you'll do better than your parents, your children will do better than you, and so on — is core to the American dream, but is far from a guarantee.

What they did: A new analysis from the Census Bureau and Opportunity Insights, a research group at Harvard University, seeks to measure intergenerational mobility at the county level.

Researchers compared the average household income at age 27 for Americans born to low-income families in both 1978 and 1992 to get a localized picture of changing opportunities over time.