NEW YORK (CNN/Money) - The number of workers with flexible time schedules has been dropping, even though some studies contend such schedules increase productivity, says a new report.

The number of full-time wage and salary workers 16 or older on flexible schedules dropped to 27.4 million in 2004 from 29 million in May 2001, reported USA Today on Monday, citing a July report from the U.S. Department of Labor.

The report said there are two reasons: companies are getting rid of flexible schedules; and workers are afraid to ask.

According to a 2005 study from the Society for Human Resource Management, 56 percent of companies offered flexible schedules in 2005, compared to 64 percent in 2002.

Big corporate layoffs, such as Hewlett Packard's plan to axe 14,500 jobs, have made workers nervous about asking for more lenient scheduling.

"Today, if you ask, you may be the next out the door in the next layoffs," said Jennifer Openshaw, CEO and founder of Family Financial Network, a financial planning company based in Los Angeles.

For more stories about the economy, click here.