The Office of the Director of National Intelligence (ODNI) reports that that security clearance eligibility fell by 4 percent in 2016.

The annual report includes the number of government employees who held security clearance at each level as of Oct. 1 in the preceding fiscal year and the number who were approved the previous year. It also contains the same data about government contractors.

According to the report, the 4 percent decrease applies to security clearances that are both “in access” and “not in access.”

The report also said that IC agencies are still facing a significant backlog for periodic re-investigation, which it said is caused by the limited number of background investigators that available. The IC also has difficulty in clearing individuals with unique or critical skills, who often have foreign associations that take time to investigate and process.