How do I set default time interval on all exchange calendars from 30 min to 15 min ?

[subnet11]

Exchange 2003 - SP2

Good morning -

How do I set the default time interval displayed on everyone's
calendars from 30 minute blocks to 15 minute blocks. We know how to do
it individually through Outlook on a per-user basis, but we want to
change this setting globally for all users in the exchange
organization.

Thanks in advance for your help !
subnet11