KPI criteria calculation

Dear friends,
I need your assistance with KPI (Key Performance Indicators)
How calculate average room rate for the entire period? (Formula)
How calculate average occupancy for the entire period? (Formula)
How calculate revenue per available room for the entire period? (Formula)
Many thanks!

@Sss Please check the below articles about list of KPI’s for Front Office Department and also other formulas.

https://setupmyhotel.com/component/tags/tag/front-office-formulas.html

Setupmyhotel.com So many thanks!