Update all snapshot data, really?

When the 'Reports> Admin> Administer Data Warehouse
Update All Snapshot Data' button is clicked, does it update the
snapshot data for all of the active project areas in RTC? Or is the
data updated for the single project area the admin is logged into?

I am trying to figure out whether we have to log into
n project areas and press the button
n times for a manual data warehouse
update or if we only need to log into 1 project area and press the
button once.

Thanks!

When the 'Reports > Admin > Administer Data Warehouse > Update All Snapshot Data' button is clicked, does it update the snapshot data for all of the active project areas in RTC? Or is the data updated for the single project area the admin is logged into?

I am trying to figure out whether we have to log into n project areas and press the button n times for a manual data warehouse update or if we only need to log into 1 project area and press the button once.

Thanks!