Can someone help me with my stats?

[YTV]

Ok I just started keeping track of my stats a few weeks ago, and need help calculating them.

I have 100 Sit n Go's $10 + $1

1st - 12
2nd - 13
3rd - 15
4th - 14
5th - 13
6th - 11
7th - 9
8th - 6
9th - 6
10th- 1

I have placed ITM 40 times so that calculation is easy.

ITM - 40%
ROI - ?

How exactly do I calculate my ROI?
I have invested $1100 (11 x 100) and have calculated return of $1290 ((50 x 12) + (30 x 13) + (20 x 15))
So I have a return of $190 on $1100 investment? 17.27% ?

Also what is the best way to keep track of them: month to month, groups of 100 or 1000? I currently did 150/month doing 1 table at a time, I will start doing 2 tables for the next month and compare results.
I started with $50 and $5 + .50 and moved to the $10+$1 at $220, my balance is now $440 and Ill start the $20 + $2 probably tomorrow.

Thanks for any help anyone can offer me.