We don’t know exactly why these men followed such a wide range of work patterns during what economists call their “prime earning years.” But we think increasing labor market precarity – which researchers say is driven in large part by increases in layoffs and decreases in unionization – played a big role.

For example, we found that men who worked as “operators, fabricators and laborers” or in “precision production, craft and repairs” were at greater risk of unemployment. These are jobs that provided our own grandfathers with good, well-paying work, but they are also jobs that have become increasingly rare since the 1970s.