A factory worker loses his job when the plant closes. A middle-class family declares bankruptcy after medical bills pile up. Downward mobility is movement to a lower social class. It can happen to individuals or to whole groups. It is less common than upward mobility in stable economies, but it is more common than many people think.

Sociologists measure mobility by comparing a person's class position to their parents' or to their own earlier position. Downward mobility can be intragenerational (within one lifetime) or intergenerational (across generations). Economic recessions, deindustrialization, divorce, illness, and addiction are common triggers.

Drivers

• Job loss in declining industries
• Medical debt and lack of insurance
• Divorce or family breakup
• Economic recessions and housing crashes
• Incarceration and its collateral effects

In the U.S., downward mobility has become more common since the 1970s. Many children now earn less than their parents did at the same age. The trend challenges the cultural belief in endless upward progress.