The number of contingency workers is steadily rising and is projected to make up 10 percent of the U.S. workforce in the next two years, according to a study by Staffing Industry Analysts.

Employers in information technology, the pharmaceutical industry and engineering will be among the biggest gainers of contingency workers, according to Barry Asin, chief analyst for the Los Altos, California-based research and analysis firm.

The study, which was released Wednesday, May 2, polled contingency managers, directors and procurement specialists from 170 companies with upwards of 1,000 employers.

Contingent employees currently account for 8 percent to 9 percent of the U.S. workforce, Asin says. But given the large number of workers that this employment base involves—each day, there are approximately 2.6 million individuals referred for jobs by staffing agencies—even a small shift can translate into major operational and logistical projects for HR executives across the country, he says.

The rise in contingent workers is attributed to the flexibility that they provide to large employers.

“Companies don’t always know what the appropriate number of employees will be when handling new projects, like expanding into new lines of products or new markets,” Asin says. “A contingent workforce gives them the ability to do some fine-tuning,”

Almost 80 percent of the companies that participated in the survey said they will increase their contingent workforce. Even employers that are traditionally less reliant on contingent workers, such as those in retail, are getting into this arena.

—Gina Ruiz