SAN DIEGO (MarketWatch) -- You will have to pardon Paul Kasriel, chief of economic research at Northern Trust in Chicago, if he hasn't been the life of the party over the past seven or eight years.

The 60-year-old economist, tapped in 2006 as the top economic forecaster by Arizona State University's W.P. Carey School of Business, has spent a good deal of that time trying to warn anybody who would listen about such things as excessive household debt while taking a jab or two (or three) at then-Federal Reserve Chairman Alan Greenspan. "Illusory" is how, in October 2004, Kasriel described the wealth created by Greenspan's interest-rate cuts in one of his edgy and somewhat irregular reports dubbed, "The Econtrarian," which are available on Northern Trust's Web site. A few months later, as household spending continued to sizzle, he wrote, "Today's 'partying' in terms of a disproportionate share of national output being 'consumed' by the household sector is a recipe for a 'hangover' tomorrow."

And in case you are wondering whether Kasriel has any regrets about having provided less-than-rosy outlooks that challenged conventional wisdom while others were celebrating record home sales and soaring stock prices he doesn't. "I look at the numbers and I have a sense of history," he says, as the sound of wind causes his voice to fade in and out during a telephone interview while he was on a sailboat on Lake Michigan, where he spent this past week.

Sailing on that lake, known for its unpredictable conditions, is an appropriate hobby for an economist like Kasriel. He believes sailing makes him a better forecaster. And as a forecaster, he is concerned more than ever about the economy, which he believes could be headed toward a "painful" recession. His analysis confirms the anecdotal evidence presented earlier this year in my column and blog items that suggested Americans are living well beyond their means. "I don't make up the numbers," Kasriel says. "And since the late 1990s, I've been seeing trends that are very disturbing."

He is particularly alarmed at the relationship between personal disposable income and personal consumption expenditures and residential investment expenditures. That is eco-babble for the amount of money people take home after taxes minus the amount they are spending on everyday goods and services and what they spend on buying and fixing up their homes. According to that calculation, Americans have been running deficits in six of the past seven years.

Prior to the recent, unprecedented string of deficits, Kasriel says there have been only seven other years American households have been so upside-down in their finances since 1929. Two of those were during the Great Depression. Three more were just after the end of World War II. Another was in 1955, then again in 1999. That leads to an obvious question: If they can't afford it, how are people continuing to spend as Thursday's report of retail sales suggested they are continuing to do as if all is well?

The answer, which has become all too obvious in recent weeks and months, Kasriel says: They appear, in large part, to be borrowing against their homes, which will become less available as a piggy bank going forward. "Households are going into debt like never before," he says. They also have been net sellers of stocks. All of this means, Kasriel says, that there will be less cash for things we like to buy.

As an economist, however, he is well aware that others might not agree with his interpretation of the numbers. "There are people who deny man walked on the moon, and there are people who will deny this, too," he says. "But the data are overwhelming that households are spending more than their income." And, besides, he says, "If everybody else thinks the way I do, I get nervous." Needless to say, he isn't, which means maybe you should be.