The data [1] says that the gov is fairly spread out. According to the OPM site, 7.4% of USDA employees work in the DC area. California has more USDA employees (10.3%) than DC.

Including all agencies, _87%_ of all federal employees work outside DC. Additionally, the percentage of DC workers seems to be going down over time, at least according to their data going back to 2016.

[1] https://data.opm.gov/explore-data/analytics/location