Why does winning lower my rank?

[HowToPlay]

@_KoBa

Your “current” rating is the rating that everyone sees and is used when match making and computing handicaps. When you finish a game, we add the game to the list of games, and compute your new “current” rating by applying the results of those games to your “base” rating. When recomputing, we also use your opponents’ “current” ratings as opposed to simply the ratings they were when the game originally concluded

So when your win, your rank is counted by your last 15 ranked games (or last 30 days if ain’t that active,) based on what are your previous opponents rank now.

Have ya endured a losing streak lately or simply lost against someone whos lost few sones after your game? Those can have big impact when counting your tally

Perhaps this is why. You noticed a little decrease.