This is actually fairly simple math. The numbers they use INCLUDE the huge majority of persons who ALWAYS report in person, because they are ineligible for telework or remote work.Regardless, I still think its BS.
80% of their time was spent in-person? Laughable Unless the "in-person" part means they actually were inside their home instead of at Target or building their deck.
There are about 2.7 million federal workers and about 300,000 of them work in the DC metro area. Most federal workers are never going to be working from home. Of those who are teleworking - most of those are in a hybrid category of working either from home or a designated remote place some part of the week - or in person, in some staggered desk sharing mechanism - the rest of the time.
It is not hard to figure that the total in person numbers would be high. Since only a portion of those eligible for telework make use of it - and most of it hybrid - I am surprised it isn't a little higher, since you are averaging their hours with those not teleworking at all.