A local bank executive wrapped up an interview on radio the other day with a blast at the press for allegedly causing the severity of the current economic slowdown. It is a recurring theme among some officials in the area's real estate industry, who contend that so-called negative news stories about the economy have hurt sagging home sales.

Concern about the downturn in the local economy appears at times to be bordering on hysteria as more indicators confirm that the boom of the 1980s is over. Unable or unwilling to determine the root causes of the downturn, some executives are lashing out at convenient targets, including bank regulators who have been accused of creating a recession by forcing banks to follow prudent real estate lending policies.

This kill-the-messenger mentality is counterproductive and stands in the way of any serious attempts to determine either the duration or severity of the slowdown. The publication of a new report by Cognetics Inc. of Cambridge, Mass., is not only timely but valuable in fostering an understanding of why the boom went bust here and in other metropolitan areas.

Although the report, which was prepared for the National Association of Industrial and Office Parks, deals primarily with the slump in the office market and with future space needs, it is instructive for what it says about key factors that shaped the economic boom of the 1970s and 1980s.

"The boom is over," proclaim the authors of the Cognetics report, "America's Future Office Space Needs." The boom in this case refers to more than just the explosive growth of office construction nationally, as key segments of the report make clear. "Virtually all of the demographic, technological and sociological imperatives that created {the boom} have either moderated significantly or, as in the case of all-important work force growth, reversed themselves completely," according to Cognetics President David Birch and his associates, who helped develop the study.

That is the very essence of what is taking place in metropolitan Washington, where the economy has been driven so extensively by growth in the real estate industry and a broad services sector. The key factors underlying their growth and gradual decline nationally are explored in considerable detail in the Cognetics report. It is must reading for those who are still grappling with two fundamental questions about the local economy: What caused the slowdown and how long is it likely to last?

To be sure, overbuilding and the unlimited flow of capital into commercial real estate played major roles in creating the region's depressed office market. And certainly a drop in consumer confidence nationally is a factor. But as the Cognetics report points out, to understand the sources of the slowdown, we must begin by understanding the causes of the recent boom. "The trends which were most forceful in instigating the office boom were basically demographic, not economic, in nature," the report's authors assert.

Specifically, they point out, the participation of women in the work force grew at a very rapid rate in the past three decades. In the meantime, a surge in population growth was fueled by the baby boom, and this group, say the authors, needed cars, first houses, appliances and places to work -- all major factors contributing to economic growth. Almost 50 percent of the office space built in the history of the United States was constructed in just the past 10 years. The most obvious cause for this boom was the addition of the "baby boomers" to the work force, according to the Cognetics study.

In the meantime, technological developments that emerged during and immediately after World War II -- the jet engine, the computer and the satellite as a means of communications -- altered how the world did business in very fundamental ways and were felt most during the 1970s and 1980s, the report shows. "These sharp gains in the ability to travel quickly and to communicate and compute cheaply explain much of our ability as a nation to develop a host of rapidly growing firms... . In other words, technology-based growth is now found everywhere and is predominantly in the service sectors -- the sectors that need office space."

The confluence of all these trends in one relatively short period created an "unparalleled need" for office space, says Cognetics. Even so, "overzealous developers and investors burdened many markets" with an excess of office space.

Sound familiar?

But alas, the very trends that generated the 1970s-1980s boom "will, we suspect, cause its reversal," the study's authors predicted.

Indeed, we already are seeing the reversal. The baby boom is over and the number of new entrants in the work force began declining in the 1980s. The labor shortage here attests to that. Meanwhile, women increasingly are withdrawing from the labor force to raise families, so female participation in the labor force is expected to level off sharply. In fact, labor shortages are expected to grow worse in the 1990s. Thus the sources of demand for office space are evaporating. In the meantime, insurance companies, pension funds and banks "are already figuring out that the boom is over." Hence, concludes Cognetics, "We can expect to see a major drop in the need for office space in the next 10 years." A conservative scenario shows that total office construction needs in the United States will be only 138 million feet over the next 10 years -- less than 10 percent of what was built in the 1980s, according to Cognetics.

Indeed, say the authors of the study, it's important to realize that this isn't just another short-term real estate cycle but a "fundamental structural shift, driven by all the basic trend reversals" noted earlier. "It is a shift that will persist beyond the year 2000."

Certainly that has profound implications for the local economy, where office employment is projected to decrease by more than 109,000 to about 375,000 between 1990 and 2000. The area has an estimated seven-year supply of office space to be filled before it reaches an acceptable vacancy rate of 6 percent.

Washington is still expected, however, to provide some of the better opportunities for office construction over the next 10 years as companies with specific needs seek to expand.

Perhaps the lesson to be learned from all this can be found in the following from Cognetics: "Investors and developers will have to be much more informed, selective and sophisticated in their choices of what to build and buy. They will have to understand not only real estate, but also how real estate is affected by everything from fiber-optic cables to fertility rates."