It now appears likely that much of the 1996 presidential race will be fought on traditional class-warfare turf. Republicans will proclaim economic growth and the importance of controlling government sprawl, and President Clinton will claim the GOP is damning the poor and favoring "the rich."

Nineteen ninety-six, however, promises to be a last hurrah for the class warriors. For months, Labor Secretary Robert Reich has been peddling the idea that the middle class has been slipping backward since the 1970s or 1980s -- by which he justifies greater government involvement in the economy. This claim, however, runs head on into contrary evidence.

The idea (promoted by politicians of both the left and the right) that Baby Boomers and Generation Xers are falling from the middle class in great bunches, even trailing behind the living standard of their parents, is, in aggregate, complete rubbish. In 1993, economists Richard Easterlin, Christine Schaeffer, and Diane Macunovich compared the economic status of young Americans with that of their parents. They carefully adjusted for differences in the number and age of family members, took inflation into account, and then calculated income available per adult equivalent. Their results show that today's young families are, on average, about two-thirds better off than their parents were at the same age. Another recent study on this subject by Urban Institute and Congressional Budget Office researchers came up with similar findings: Inflation-adjusted pretax income per Baby Boomer was 55% higher in 1989 than it was for their parents 30 years earlier.

It is thus absolutely false to argue that Americans have less economic wherewithal than they used to. Yet, undeniably, many Americans -- elites and rank-and-file alike -- are convinced that we live in a time of stagnation rather than the reality of record prosperity. Why?

Lots of reasons. One of the biggest is the revolution of rising expectations. The consumer appetites of many Baby Boomers and Generation X-ers are outracing reality and a reasonably growing economy.

Today's average new house is twice as big as one built after World War II. There are now more registered vehicles in the U.S. than licensed drivers. The average American now consumes literally twice as many goods and services as back in 1950. (In fact, the poorest fifth of the U.S. population today consumes more than the typical family did in 1955.)

But Americans take more things for granted today and view as essentials many things that used to be considered luxuries. Because of this, even today's material abundance feels like "not enough." Rising expectations aren't necessarily unhealthy, but they do need to be controlled. Our problem today in this area is not so much one of economics as of psychology.

Another reason so many Americans have accepted the idea that "we aren't getting what we deserve" is because a twisted set of national statistics encourages that conclusion. Today's official measures of family income, poverty and prosperity are a mess. The government data simply haven't kept up with rapid changes in technology, demographics and social patterns.

An example that has recently begun to sink into the national consciousness concerns the Consumer Price Index. Used for the critical task of discounting increases in family income to account for inflation, the CPI is a fossilized construct that for years has underestimated real income growth by about 1.5% annually (according to the blue-ribbon Boskin Commission). The implication of this is that median weekly earnings for full-time male workers didn't fall 12% from 1979 to 1994, as the gloomy official numbers suggest -- they actually rose 14%. Women's earnings over the same period didn't rise 7%, as published, but actually zoomed upward 35%. And the number of officially poor persons is 15 million, not 38 million, under the CPI corrections proposed by the Boskin Commission's distinguished economists.

Many other problems bedevil popular interpretations of income statistics. For instance, the figures on cash earnings that are regularly trumpeted by economic declinists completely ignore the doubling since the early 1970s of worker compensation taken in the form of fringe benefits. The increase in noncash income is even sharper on the governmental side, where every year, hundreds of billions of dollars worth of health care, food stamps and housing transfers -- which didn't exist in 1970 -- are pumped into the economy, unacknowledged in the national income statistics.

Erroneous comparisons of demographic apples to oranges are another common mistake of those who use weak official income figures to grind their programmatic axes. When tracing median family incomes over time, you must be sure you are looking at the same kind of household. The characteristics of the average family (configuration, number of members, average age, etc.) have changed a lot over the decades, and if you don't match equivalent households when you compare their income, you will be misled. Families have become considerably smaller, for instance. The average family had 12% fewer members in 1993 than in 1970. And a smaller family with the same income is actually richer. When you correct the income statistics for family make-up, you find that average incomes are clearly up since the early 1970s, not down.

Today's raging debate on "fairness" and family incomes repeats earlier controversies. In her keynote address to the 1988 Democratic National Convention, soon-to-be-Texas-governor Ann Richards read a letter from a "young mother in Lorena, Texas," who mourned that her "worries go from payday to payday.. . . I pray my kids don't have a growth spurt from August to December so I don't have to buy new jeans. . . . We ponder and try to figure out how we're going to pay for college, braces, and tennis shoes." In a gush of response to the Richards speech, editorial pages and talk shows across the land buzzed about the "death of the American dream." One election cycle later, Bill Clinton rode this theme of middle-class anxiety right into the White House.

So it's worth remembering that, after the klieg lights were turned off and the conventioneers went home, an enterprising reporter tracked down that struggling family in Lorena. It turned out they had savings in the bank, lived in a house they owned and had an annual income of $68,000 in current dollars. Granted a $68,000 income can leave a family, at times, a little "pinched." But can someone in this situation rightfully claim that decent family life is beyond their reach? More importantly, has it become the responsibility of the government to make daily life free of trade-offs for such families?

Count on Mr. Clinton, Mr. Reich and others to make such an argument over the next 10 months. Better keep a few grains of salt handy.

Mr. Zinsmeister is a fellow at the American Enterprise Institute and editor of The American Enterprise magazine.