How does the ranking system work for fifa 09 online games

If we are talking about the same thing, for every ranked victory or loss you get, you win or lose skill points respectively. you start on i think 500 and about every 100 points thereafter you rank up. if you get up to about 650 which is level 2 then drop down to 500 your rank will remain the same until you pass the level 3 marker which is 700 i think. the amount of skill points you receive or lose depend on the oppositions skill level, the teams used and the score so if you lose to someone who is level one and you are level four then you will probably lose about 30 points but vice versa, you gain 30 points.
hope that helps :)