Managing your bankroll
Measuring results: ROI, yield and variance
5 min
If you don't measure honestly, you can't tell skill from luck. A few simple metrics keep you grounded.
ROI and yield
ROI (return on investment) is your net profit divided by the total amount you staked, as a percentage. Yield is the same idea expressed over total turnover. If you staked 100 units across a season and ended +8 units, your yield is 8%.
A sustained yield of even a few percent is genuinely good — professional sports bettors often live in low single digits. If your tracker shows 30%, you almost certainly haven't run long enough yet.
Why win rate alone lies
Counting how often you win is misleading without the odds. Winning 70% of your bets at short prices can lose money; winning 40% at long prices can be hugely profitable. A bet is only "good" relative to its price — never judge results by hit rate alone.
Variance and the short run
Variance is the natural swing of outcomes around your true edge. Even a profitable approach will have losing weeks — sometimes losing months. The short term tells you almost nothing:
- A 10-bet sample is noise.
- Hundreds of bets begin to reveal a real signal.
Track every bet — stake, odds, result. Judge the process over a large sample, not the last few slips.