Q&A with
Frank P. Stafford
Director, ISR Panel Study of Income Dynamics
Research Professor, ISR
Professor, U-M Department of Economics

 

Q. The Panel Study of Income Dynamics is now the longest-running panel study in the world. You've been following up to four generations of the original study families. If you had to identify one main insight from this uniquely long-term look at human behavior, what would it be?

A. People's lives change more than most of us might think. The study shows that there's a great deal of volatility over time in almost every aspect of life—income, employment, marital status, living arrangements, time use, even weight! And over the years, the study shows that these changes have become more dramatic. The degree of volatility is much greater in the last 10 years than it ever was. Job tenure, for example, has become a lot shorter today than it was in the '70s or '80s, and the more job turn-over people experience, the more likely they are to experience health problems, divorce, moves and other major life changes.

Q. How does the study assess economic well-being?

A. When the study began, its traditional focus was on income. But over the years, we've realized that income is just one important element in economic well-being. We've also realized that the elements contributing to economic health are not as closely tied together as most people think. For example, among families in the top income group, many don't have pensions. Others haven't accumulated much wealth—they've made a lot of money but they've spent it instead of saving it. There are some families who are in the top-income group because they have multiple earners who pool resources. And there are even some families in the top income group who don't have health insurance! So it turns out that economic well-being involves a lot more than just income. To be okay economically, families have a lot to juggle.

Q. What have been the most important findings from the study?

A. Early on, the founder of the study, ISR economist James Morgan, discovered that although about the same percentage of the population lived in poverty year after year, the identity of those people changed. In other words, people moved in and out of poverty. There wasn't a 'culture of poverty' in which the same families stayed poor for generations. At first, this kind of mobility makes it seem as if America really is a land of opportunity, where people do move up—or down—the income ladder. But recently we've been able to look at intergenerational patterns of change in families. And we have found there's a great deal of carry-over in some areas; there's a lot less movement than we thought we'd see. The earnings of today's male boomers, for example, are the same as their dads' earnings when their dads were the same age. So in a way, the more things change, the more they stay the same.

Q. What's coming up for the study?

A. We're going into the field again in 2007. We'll be collecting what we call 'core' data on health, wealth, income and jobs, but we'll also be doing some new things. One of these is that we'll be collecting information on early childhood health using a health history calendar to see whether health problems in early childhood carry over into adulthood, and if so, how. We'll also be conducting a follow-up to the Child Development Supplement, looking at about 1,000 young adults ages 18-22 to look at the transition to adulthood. Then, starting in the fall of 2007 and through the spring of 2008, we'll be collecting time-diary information for the third time from teen-agers in the study. This should be really interesting because we'll then be able to look at changes from earlier groups of teens in terms of how they're doing and the ways they spend their time.