you are correct. 9,900 employees are not that many field investigators. There are support staff and reviewers that do a lot of work behind the scenes. I am very thankful for the record searchers that do a lot of the hard work chasing down and reporting records that I used to be required to chase.
I don’t know the actual number of current field investigators - but out of 9,900, approximately 9,000 might be active with the field work.
The overall federal background investigator numbers are also skewed because NBIB contractors can be “counted” more than once. There was a time in the 2000’s that 16.000 was the magic number for background investigators for all background investigations in the federal government. That would be 16,000 individual investigators - not credentials issued.
See, a NBIB contract investigator may also be “credentialed” for one or more of the other federal agencies conducting background investigators. So a contractor might be counted two and up to nine times in the over all count for all of the government. I personally know three contract investigators who have multiple credentials, to include NBIB creds, but normally work “alternate contracts”.
This was one of the concerns in Congress when DoD wanted to do just DoD clearances – DoD wanted to share NBIB’s contractors with NBIB.