how to compute for average rental period

[Catherine Javier]

Hello there BP Community!

We are new in Airbnb. We have a property in Tacoma and started MTR last year, we were so used to Furnished Finder and were a bit overwhelmed with Airbnb. 
We do a hybrid MTR and just started STR in between. This might be a silly question but we are really not sure on how to compute for the average rental period. Our goal is to do the STR loophole (less than 7 days or less.)


Do we just add all the numbers of rented dates and divide by the total number of guests or tenant?

Or.. let’s say we have 3 guest who stayed 60-90 days and 15 guests less than 7 days?

Thank you in advance!