I do once a week in the summers, Monthly on months without long term breaks and Bi-Weekly December and march, this way I can big chunks instead of just one page a week so I can get somewhere with my story. I don't want to be stuck in story-line limbo so I try to stay consistent. I can do around 5 pages a week in summer, 8-10 pages bi-weekly months and around 15-25 pages a month for regular months, so I can do one chapter in about a month.
Side Note: By story-line limbo, I mean being stuck in the same arc for years because of small amounts when it comes to updates. It's a big problem for me and the reason I don't really color.