Ive known a couple empty buildings on base, it has nothing to do with employment or teleworking, they are basically condemned and awaiting the slow government process of approval to be torn down and replaced.
Some years back the entire site of our compound went through asbestos abatement - at any given time, as much as half of the building was empty. But never fear! We were still there - just either in trailers or other offices we rented out - or in a few cases, crammed into another building on site.
Occupancy rate doesn't say anything.