Rank for Slayer & Swat: performance or win/loss

Being the top player on a losing team lowers your rank. Even if you go 20kills-10deaths have the best K/D ratio however you have a guy on your team that 2kills-15deaths and another team mate who went 5kills-13deaths.

Should the 20kills-10death guys rank go down cause his team mates he didn’t pick suck?
Or is it correct that his rank goes down cause he didn’t win the game.

SWAT is a team based gametype. All team based gametypes should be based on W/L regardless if one person greatly out performs the rest of his team. If you decide to go into SWAT by yourself you’re taking the risk of possibly getting teammates who may not do well.