User blog comment:MaqiiCz/Ranked Games/@comment-4057638-20130712071405/@comment-3014924-20130712132913

It's a hidden value for matchmaking purpose, AFAIK. Say you play duo with a higher ranked guy, your score would go up and you'd face stronger opponents than your actual division, which kinda sucks as you are less likely to carry or contribute well to your team victory.