Their frustration helps explain not only this year’s disturbing presidential campaign but also Americans’ growing distrust of nearly every major societal institution, including the federal government, corporate America, labor unions, the news media and organized religion.

Yet the data also helps point the way to some promising solutions.

It begins with children who were born in 1940, less than a decade after the publication of Adams’s book, “The Epic of America.” The researchers went into the project assuming that most of these children had earned more than their parents — but were surprised to learn that nearly all of them had, said David Grusky, one of the researchers, also of Stanford. About 92 percent of 1940 babies had higher pretax inflation-adjusted household earnings at age 30 than their parents had at the same age. (The results were similar at older ages and for post-tax earnings.)

The few 1940 children who earned less than their parents were also, for the most part, doing just fine. They were generally earning less because they had grown up rich — children of top corporate executives, say, who became, or married, doctors, lawyers or professors.

Achieving the American dream was a virtual guarantee for this generation, regardless of whether people went to college, got divorced or suffered a layoff. Why? Because they spent their prime working years in an economy with two wonderful features. It was growing rapidly, and the bounty from its growth flowed to the rich, the middle class and the poor alike.

Not even the oldest baby boomers, born in the late 1940s and early 1950s, would be quite so lucky. Economic growth began to slow as they were entering the job market in the 1970s, thanks in part to the energy crises. Still, more than three-quarters of these early Baby Boomers would ultimately make more than their parents.