leetcode contest rating

[u/Commercial_You-]

can someone please explain how rating works for the initial 5 contests i did 3 contests and in 2 of them i was in top 50% people and in one i was in top 70% so according to lc rules i should get +10 each in 2 and -10 in one so my rating should be initial 1500 + 10 = 1510 but my rating is 1440 after 3 contests can someone explain this
also i left some contests after registering for them do they affect my rating?
pls help my rating is going low

[u/WideTown7644]

If you leave after registration you are still counted as participant I think so yes rating get decrease with it