I remember well the huge chart dragged out onto an easel every month on the platform during the 60s. Average hours. Bible studies. Subscriptions. Mags. Books. RV/backcalls. Stern warnings for slackers who could be guilty of bloodguilt!
100 hrs a month for pioneers. Timed coffee breaks.
One CO (Andy Laguna) told me in the 90s he wouldn't even consider appointing new servants who didn't average 15 hrs per month with at least one study.