A worked example
You took 2.10 and the market closed at 1.95: CLV = 2.10 / 1.95 − 1 = +7.7%, you beat the close. Had it closed at 2.30, CLV would be 2.10 / 2.30 − 1 = −8.7%.
How the calculation works
CLV = odds taken / closing odds − 1. Use the closing price of a sharp bookmaker such as Pinnacle, ideally with its margin removed (devigged). Against the raw close, CLV is flattered by roughly the margin built into that price; against the devigged close it is not. On TipsAudit, value flags are graded against the devigged Pinnacle close.
What this result does not tell you
One bet's CLV says little: closing prices move for many reasons. CLV becomes meaningful as an average over hundreds of bets, and only against a sharp closing line; a soft bookmaker's close is a much weaker benchmark.
Common questions
What is a good CLV?
Any consistently positive average. Beating a sharp close by +1% to +3% on average over hundreds of bets is strong evidence of skill. On a few dozen bets, even +10% can be luck.
Why use the closing line and not the result?
Results are dominated by chance over short samples, while the closing price aggregates the information available up to kick-off. Bettors who beat it on average tend to profit in the long run, which is why bookmakers watch it.
Should I devig the closing odds?
Yes, if you can. Remove the margin from the sharp close (for example with the no-vig calculator) and compare your odds with the fair closing odds; otherwise your CLV is overstated by roughly the margin.
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