You've heard about blue-collar crime, white-collar crime, and computer crime. Robert Half International, the recruiting firm, has found another form of workplace larceny: time crime. After a continuing 10-year study, Robert Half has concluded that employees steal $161 billion worth of time a year, an average of about four-and-a-half hours per week per worker.

We're not talking about chitchat around the coffee machine, either. Consider the man who ate food he was allergic to in the morning so he could take the afternoon off; or the administrative assistant who spent three hours a day selling cosmetics to fellow employees; or the two cohorts who used a locked filing cabinet between their desks to hide an electronic chess set, which they played during the day.

Japan, meanwhile, has the opposite problem. Despite the efforts of the government and labor unions, Japanese workers continue to work too hard. Not only did working hours grow longer in 1984, according to recently released figures, but private-sector Japanese employees took only 56% of the paid vacation days to which they were entitled.

This is, of course, no consolation to American employers. Short of hiring Japanese workers, Robert Half recommends keeping a watchful eye on supervisors. "They're the ones who are usually at fault," says Patrick Southerland, president of Robert Half of Washington, D.C., Inc. "They set the tone, and should lead by example."