“Most Americans partake in the benefits offered by these new technologies, from smartphones to better dental care,” Professor Shapiro said. Still, he acknowledged, “somehow this impressive progress has not translated into greater economic security for the American middle class.”

In key respects, in fact, the standard of living of most Americans has fallen decidedly behind. Just take the cost of medical services. Health care spending per person, adjusted for inflation, has roughly doubled since 1988, to about $8,500 — pushing up health insurance premiums and eating into workers’ wages.

The cost of going to college has been rising faster than inflation as well. About two-thirds of people with bachelor’s degrees relied on loans to get through college, up from 45 percent two decades ago. Average student debt in 2011 was $23,300.

In contrast to people in other developed nations, who have devoted more time to leisure as they have gotten richer, Americans work about as much as they did a quarter-century ago. Despite all this toil, the net worth of the typical American family in the middle of the income distribution fell to $66,000 in 2010 — 6 percent less than in 1989 after inflation.

Though the bursting of the housing bubble and ensuing great recession takes a big share of the blame for families’ weakening finances, it is nonetheless startling that a single financial event — only a hiccup on the road to prosperity of Americans on the top of the pile — could erase a generation worth of progress for those in the middle.

Though the statistics may be startling, the story they tell is, unfortunately, not surprising. It is the story of America’s new normal. In the new normal the share of the nation’s income channeled to corporate profits is higher than at any time since the 1920s, while workers’ share languishes at its lowest since 1965.

In the new normal, the real wages of workers on the factory floor are lower than they were in the early ’70s. And the richest 10 percent of Americans get over half of the income America produces.