How to calculate how many days foreign residents of Bolivia can stay out of the country

by Sarah McCleave
(La Paz, Bolivia )

Hello! I am a resident in Bolivia (my family are from New Zealand and Australia) and I've been told you are permitted out of Bolivia for a maximum of 90 days per year.

As my family is so far away, it is only practical to visit them for a long period plus we have several trips around South America planned, so we can see this beautiful place.
Is anyone able to help me how to work out the 90 days? I am not sure if this includes the day that you fly/bus out or fly/bus back in to Bolivia? Or is it just FULL days out of Bolivia?

Any help would be appreciated!
Thank you, Sarah