As Flipper said, you need to fade the best way you know how to for your circumstances. I slowly decreased my time by only going out with certain people (a friend who would invite me, whatever) or by going on a study with my mom once or twice a month. I also got very "busy" with work (I did work 2 jobs temporarily...that was part of the fade). So I could be honest with how many hours I spent...and I always made sure I said I placed NOTHING. The reason for this (beside the fact that it was true lol) is that they can't count what you don't place. Why give them the numbers? Eventually, I just stopped going on the studies altogether and just made myself unavailable for service when invited "Oh, Saturday?? Sorry, I'm working! Maybe Sister Over-Zealous can go...".
I only started getting hounded when I wasn't turning in a slip. That's when they start to bother you. "Hello, Kool Jo, this is Brother Brown Nose. I was calling to see if I could get your Field Circus time for the month of July...Oh you didn't get any? There had to have been ONE HOUR the whole month that you spoke to SOMEONE about Jehovah...". When this was posed to me, I said "I suppose...I mean, I don't want to say there definitely was if there wasn't. I didn't keep track. I don't want to LIE on my Field Circus report...Do what you think is best". The following month, I claimed I was so busy I just couldn't get out and that we aren't allowed to talk religion at work...and I don't associate with them outside of work because they're "bad association". After that I just stopped answering the phone. They came around a few times when I wasn't home (my father alerted me), they planned on coming around a few times (my father alerted me so I could be out lol), and there was a time or two they actually caught me and I simply told them I was busy. When they tried to pin me down for a Shepherding Call, I told them I didn't know what my schedule would be like, that I was working two jobs, and that when I wasn't working I was either sleeping or running errands. I'm just too busy.
Eventually, they quit trying. And it's been peaceful bliss ever since.
I don't know your family situation (if you're married, have children, or whatnot), but the best thing I did was move away from the area and not give a congregation to forward my stuff to. I didn't give my parents my address until after I moved so that if they were asked they could honestly say they didn't know. I haven't been contacted, haven't seen any JW's, and have been free to celebrate holidays and do what I want. That might be a solution if your situation permits it.