You can measure attendance by hours spent at a desk
replyWell if you're a devshop just billing hours of mostly low impact work then hours are very much equal to productivity.
replyNext time you're going to work for an hour, ping me, and I bet I can surprise you with how much less productive I am than you
replyProductivity is measured by economists in $/hour.
replyWhich is why two identical jobs with the same real life output have drastically different productivity.
A nursing home in Luxembourg has 5 times the productivity of one in Romania despite the services being identical and tech-unrelated.