Arena points flush calculator

Does anybody know how are the arena points calculated exactly? I barely had 100 rating and got like 250 points...I managed to hit 1k rating and I am wondering how much ill get next week. If anybody know exactly how are they calculated let me know
Thank you
This is for Icecrown realm.

from 0 - 1500 rate you will get same arena points (261).
After 1500 you can use http://www.arenapointscalculator.com/ to calculate how much you will get.