(FORTUNE Magazine) – Remember when we last had it so good? Maybe you don't. That's because the U.S. unemployment rate hasn't been this low--4.1% in February--in 30 years, and it's been under 5% for almost three years. The last sustained period of low, low unemployment was between 1965 and 1970. In 1968 unemployment stood at just 3.4%.

Of course, it was a very different world then. We were at war, for one thing, and more than three million people were serving in the armed forces in Vietnam. At home, more people worked in manufacturing jobs, and 24% of working people belonged to unions, compared with 13.9% three decades later. Men dominated the work force, and women held just over one-third of all jobs. "At that time, women were in and out of the labor force and had higher unemployment rates than men," says Cornell University economist Francine Blau. Now women workers make up a larger share of the labor force and have unemployment rates similar to men's.

The typical worker today is more likely to be in a service, managerial, or professional occupation, and is probably staring at the luminous glow of a computer terminal. Yet in one disheartening way, the typical worker's lot hasn't changed much: Household income has stagnated since the 1960s. In 1997 the median household was earning $37,005, just $4,000 more than the median household earned 30 years earlier (that's after adjusting for inflation). Real wages for less educated men have actually decreased over time, as has the real minimum wage. (Bills to raise the minimum wage to $6.15 are pending in Congress.) "More married women are working outside the home, and that has contributed to growth in household income," says Blau. "But on the other hand, we have more female-headed families. There's one adult [wage earner], not two, and women on average earn less than men."

The careful balancing act between low inflation and high consumer demand sustains today's boom economy and low unemployment. Even the fast-rising U.S. prison population makes the unemployment numbers look lower, by absorbing people who might otherwise be unemployed or marginally attached to the work force. But now the hungry labor market is even absorbing some prisoners (see previous story), not to mention the elderly, teenagers, immigrants--anyone willing to put in a day's work.

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