one thing that always really bothered me in my most sincere days, was the way some would start counting time when they walked up to the first door. so in a car group of 4, two people would start counting at the first return visit and the other two ten minutes later at the next return visit, and i never agreed how 2 people get to have an extra ten or fifteen minutes just because their RV happens to be first on the path they're going, while in reality all 4 gave up the same portion of their day to be there.
i think most adopted the practice of starting counting time upon leaving the service group.
after a while i started counting from the moment i started getting dressed for service, reasoning that from that moment on my day became different because of going in service, so in a way, thats when i started "dedicating time" out of my day to the doing of "the work".
now i just randomly come up with an ok-ish sounding number every month.