Socioeconomic status in the US harder to change than any time in past 150 years

For a certain population subset, socioeconomic status in the United States is harder to change now than at any point in recent history, according to research from the University of Pennsylvania, Princeton University, and elsewhere.

In the first long-term assessment of social mobility in the U.S., Penn sociologist Xi Song and colleagues discovered that mobility has substantially declined during the past 150 years, particularly for those born in the 1940s and later. They also found that the well-documented rise in economic inequality of the past four decades has not affected intergenerational mobility in the ways many expected it would.

The team, which also included researchers from the University of Nebraska Omaha, Northwestern University, and the U.S. Census Bureau, published their findings in the Proceedings of the National Academy of Sciences.

"Most work in this area has focused on more recent decades," says Song, an associate professor in the Department of Sociology at Penn and the lead study author. "Ours looks back to 1850, before the Civil War, and covers two World Wars, the Depression, and social changes in the racial history of the United States."

Song and her collaborators could go that far back thanks to newly available Census data. They examined information from approximately five million people, using first and last names, ages, birthplaces, and parents' birthplaces as identifiers, and then Social Security numbers in the 1940s.

For consistency, the analysis included mostly white males, with a small number of males from other racial groups. In the mid-1800s, most females didn't have jobs outside the home—the gauge the researchers used to measure socioeconomic status—or they changed their names after marriage, making them harder to track over time. Other races were underrepresented due to a low rate of linking across years in the dataset.

The researchers' analysis showed that for the study population, sons born before 1900 experienced significant upward mobility compared to their fathers. Around that time, the country was moving from agriculture to industry, and with that shift, sons stopped doing the farming their fathers had, taking manufacturing jobs instead. "Many of them migrated from farms to booming towns and cities to become operative workers, blacksmiths, bricklayers, truck drivers, and sales workers, so they achieved a higher socioeconomic status compared to their parents," says Song.

As the prestige of certain occupations diminished, this trajectory slowly began to change. Song explains with the example of a cashier.

"A cashier used to be a high-status job," she says. "In the 1850s, very few occupations had close to a 100% literacy rate. If you were a cashier, you could read, write, do some calculations. It was a small profession but a high-status job. Over time, most occupations experienced some decline in their status."

Like cashiers, typists and elevator operators and other similar professions had a different connotation in the early 20th century than they do today. "Only a few professions—jurist, health professional, scientist, architect, and engineer—have remained stable in their status," she says.

The effect becomes even more pronounced starting with the baby boomer generation and continuing through today. According to Song, that means that intergenerational ties have become tighter. In other words, children today resemble their parents more in terms of socioeconomic status than in any previous generation. "They follow their parents' paths," she says. "Their social achievements reflect their family background."

That doesn't, however, implicate the economic inequality and income polarization that has occurred in the U.S. during the late 20th and early 21st centuries. The researchers found that although income inequality has risen sharply since the 1970s, the relative trend in social mobility has stayed largely stable.

One major limitation to the work was the lack of diverse demographic information within the dataset, Song concedes. "For us to trace these changes over time, we're comparing those who were in the U.S. in the 1850s to those who are here now, but the racial composition has changed significantly," she says. "Although this is the best historical census data we have, it still excludes large swaths of the population."

In the future, she says she hopes to find other datasets, like those at the regional level, that might paint a truer picture of how non-white groups in the U.S. have fared in terms of social mobility. "I think the patterns for ethnic minorities might be different than what we see here," she says.

Despite that constraint, Song says the work can offer insight into what factors may help influence the success of future generations and how likely that success might be. "Promoting mobility by policy interventions via families is going to be a hard job. It's been stable recently, resistant to change," she says.

"It all still depends on family influence," she adds. "Like father, like son."