I lost about 30 at the end of last week and I lost about 25 yesterday.
Don’t seem to have many posts in the discussion category so not convinced it’s that.
Not particularly fussed (who needs rep when you've got 23 badges?? :p ) but interested in where they went.
See here for more information. Besides that, some topics have been moved to the new Discussion type. In the Discussion topics each upvote is worth 1 point.
Most of the Discussion topics were Question topics. In a question topic an upvote is worth 10 points. With the topic type change, the reputation is recalculated, resulting in lower reputation.
This is a side effect of the new addition to tracker but will only impact a few users and for a short period of time.