I've participated in every roulette since Train of Naught's 3rd roulette back in 2017 (so 43 roulettes.....am I counting that right? LoL. Plus I've run 3), but I'm a roulette junkie, so....
I've got you at 39, but I don't count roulettes that are abandoned rather than properly finish, and I update the list when a roulette finishes, so that doesn't include Sacul's latest yet.
Speaking of this, I feel I should go ahead and give some closure on my album roulette that I abandoned a little over a year ago.
Unfortunately, I'm not ever going to finish that one. There are a few reasons: One of the participants has since left the forum, so that's a logistical challenge. I've bought and listened independently to a couple of the albums from the suspended round, so it can no longer be scored fairly. But most of all, it would ultimately be uncomfortable for me to resume that particular roulette because of the personal tragedy that caused me to suspend it.
I'm too busy right now to run a roulette, but I hope to do one again someday. When I do, though, it will be a fresh start.