Leaflets lie on a table at a booth at a military veterans' job fair in Carson, California, in this file photo taken October 3, 2014. (Lucy Nicholson/Reuters)

Contractors will have to start collecting annual data on their veteran hiring practices in 2015, according to an updated Labor Department regulation.

The rule, released last fall, is a significant modification to a 1974 rule related to the hiring of veterans after the Vietnam War and an example of the government’s push to use data to study industry trends.

The new rule requires companies that hold government contracts worth $100,000 or more to submit annual reports about veterans in their workforce, with the first report due between August 1 and September 30 this year. The department will assess whether contractors are compliant with the new ruling or at least have a plan in place to increase their veteran hiring initiatives, and could use yearly data to spot patterns in veteran employment.

For post-9/11 veterans, the unemployment rate is still higher than that of the overall population. According to the Bureau of Labor Statistics, in December, the unemployment rate for this group was nearly 7 percent, compared with 5.6 percent for the rest of the country.

The update also streamlines reporting requirements for contractors by cutting in half the number of categories for which companies have to collect data. The Labor Department estimates that this will save companies more than $18 million over the next decade.

In addition, the rule introduces the concept of a veteran hiring benchmark. Companies need to eventually show that the percentage of veterans in their workforce is the same as the total share of veterans in the national population — about 7 percent.

There is some flexibility for companies to determine their own benchmark by setting a hiring goal based on the proportion of veterans in their state’s population. The benchmark is not mandatory, but a tool for employers to assess where they stand when it comes to hiring veterans, said Jeffrey Bozman, a contracting attorney at District law firm Covington & Burling and a former Marine Corps officer.

For Washington-area contractors, the effect of the new rule is expected to be minimal, Bozman said, since many already employ a large share of veterans.