Lanefan
Victoria Rules
That's what game logs are for.The thing is, tho', continuity of once-a-month is still a major effort to keep going past a year, if only because so much gets forgotten.

And it makes sense that long campaigns are in the numeric minority, as while one group might be in a 10-year campaign another just-as-consistent similar group might have five 2-year campaigns over the same period. Thus, despite a 1:1 correlation between the groups you've got a 5:1 correlation between their number of campaigns.