1
How much or IF your rank rises or falls is mainly based on the rank of the opponents you beat as long as you are an active player. You move up half the distance between your rank and the person's you defeat, so the higher ranked your opponent is the further you will move up the Ladder if you win the match. In other words, you can have ten wins in a row, but if your opponents were all ranked close to or behind you your actual Ladder rank will not improve much. However, playing lower ranked opponents can increase other ratings such as the win percentage and skill rating, so there are still benefits to your overall status. Please note that the percentage of rank gain may vary from League-to-League so you may not move up half the distance when you beat someone ranked better than you. Please contact the Admin team for the League if you have any concerns regarding your rank.
You can find complete details on the skill rating system at http://www.myleague.com/rating.html Read the document carefully to understand how it works.