Washington ? When baseball players and owners averted a strike Friday at the last minute, they joined a growing and record-setting trend away from major work stoppages.

Last year saw the fewest number of workdays lost to major strikes or lockouts since record keeping began in 1947. And this year is producing even fewer strike days, according to the U.S. Bureau of Labor Statistics.

Major league baseball joined a U.S. trend in avoiding a work stoppage. A fan displays his thoughts on the baseball settlement Friday before the Montreal Expos-Atlanta Braves game in Montreal. For more on the agreement, see page 1C.

“The drop in the number of work stoppages has been precipitous,” said Robert Thornton, a professor of economics at Lehigh University in Bethlehem, Pa.

After averaging 26 million lost workdays yearly due to strikes and lockouts in the 1970s, the number fell to an all-time low of 1.2 million in 2001. Through the end of July this year, major strikes caused 382,400 lost workdays, far lower than the 641,500 for the same period last year.

Experts say the reduction in strikes is due to the steady weakening of labor unions, the willingness of companies to operate during strikes, dicey economic conditions and scars left from disastrous strikes in the 1980s.

“The balance of power in labor in the United States has tilted very much in favor of employers in the last 25 to 30 years,” said Gary Burtless, a senior fellow at the centrist Brookings Institution research center in Washington and a former economist at the U.S. Department of Labor.

In 1960, nearly one out of four American workers belonged to a labor union. Now the figure is closer to one out of nine. Only 9 percent of Americans in private industry are in labor unions, and that figure has been dropping steadily.

“It’s no surprise that as (the percentage of union workers) goes down, you’ll see a drop-off in the number of strikes,” Thornton said.

A key date was the 1981 air traffic controllers’ strike, when President Reagan fired the striking workers and replaced them.

The move “totally changed the psychological atmosphere for bargaining in this country,” said Rick Bank, director of the AFL-CIO’s Center for Collective Bargaining. Before that strike, it was rare for replacement workers to be hired.

Companies “have become very sophisticated at defeating unions,” Burtless said.