How to work out your poker hourly
Add up every session's result and divide by every hour you played. Don't average each session's hourly: a 12-hour session should count three times as much as a 4-hour one.
Up $200 in 4 hours, then down $150 in 6, is +$50 over 10 hours: +$5 an hour. Averaging the two sessions' hourlies — +$50 and −$25 — would say +$12.50, more than twice too much.