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Please take a look at our guide:
Besides, in Expressions Stats Editor you can find many examples of default stats for our default HUDs and Popups. For example:
Once you have created the desired expression stat, you can insert it into your HUD with the right-click:
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Please note, the Popup/HUD should be assigned for your Game Types before rebuilding:
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After that you can use the following expression string:
WonHandCases(flop any action) / Cases(flop any action) * 100 > 44