It varies with my dogs too.
I put 5 but it could be more or less depending on
them.
I do not know what is up with Sheba but for the
last couple of weeks she has been wanting to go
outside and than back in the house 3 times just
between 5:30 and 8:00 p.m.

Rocky on the otherhand has been wanting
to go outside a lot less since the rains have started.

I guess it depends on the weather just how long
the dogs want to stay outside.