Hi, sometimes I don't understand this scoring mathematics. Actually I was noted that rating calculation seemed not so accurate, but never before I could tell exact numbers, because I didn't followed them very accurately.
Today evening I played only one game and can't find explanation to rating results:

Before game I had rating of 1825.
The game was unsuccessful for me:
DasI finishes 7th.
Rank: 1865th Rating: -37 1756.

Hmmm.... Let's try to calculate: 1825 - 37 = 1788, but not 1756 which mean that I've got actual rating down by -69 instead of -37? Can someone explain this?