Im logging results every hour for standard deviation.

Say I play three hours and it goes
Win 50 first hour
Lose 50 second hour
Win 50 third hour

Then before I leave, I play 15 minutes and win 200 in that timeframe.

How can I incorporate this into my standard deviation?

Thanks.

This is how you calculate standard deviation for sessions of varying duration. Let me know if you need the spreadsheet to do it.

Thanks Bruce

One of the few 2+2 links I have in my browser's bookmarks