Is CSR increase/decrease affected by leavers?

I recently managed to make it to rank 6 of my division in Team Arena after a series of good matches, and I was pretty excited to do so. However, during the next match, one of my teammates left about a quarter of the way through and we went from a winning position to an eventual loss. I was disappointed to find I’d been demoted back to rank 5 again.

Afterwards, I started to wonder, how exactly is CSR calculated? Because I ranked up after a win and immediately ranked back down with the loss, it could be that the game counted my match as a “fair” loss and deducted the normal number of CSR points, which feels… odd. In a 4 on 4 game mode, why should my performance be graded the same when my team is set back by the loss of a member?

The other explanation - which I think is probably the case - is that I only barely scraped my way into rank 6, so even when the system gave me less of a penalty for losing the handicapped match, it was still enough to drop me down.

But I’m not sure, so I figured I’d see if anyone here knew. Does my rate of CSR gain/loss change if the match has uneven teams?