Becareful's right, using $10 as the turnover figure is totally misleading.

If you used the $210, and the last bet lost. You'd be left with a Loss on turnover of $10/210 = roughly -5%. A much more accurate guide of your performance than -100%.

If you used $10 as turnover your record would look like this

No of selections
3
Strike rate
66%
No of bets
1
Strike rate
0%
Result
$10 loss
POT
-100%

Looks like you're betting on the wrong horse.