UC520 historical reporting and voicemail capacity

Question

Hello,
If I need to configure historical reporting which requires the mailbox capacity to be 480 or less, what effect would continuing at the prompt below have on users' current mailboxes?
10.1.10.1(config-hrdm)# enabled
!!!WARNING!!!: You are seeing this message because Historical Reporting has never been enabled on this system. You would be allowed to enable Historical Reporting only if the Voicemail mailbox capacity is less than or equal to:480 mins.
Note:If the Voicemail capacity is less than: 480 mins, and if you were to enable Historical Reporting now, you would not be able to increase it again, even if Historical Reporting were to be disabled. You must re-install the system to increase the Voicemail capacity again.
Do you wish to continue[n]? :
Current capacity:
10.1.10.1# show voicemail limits
Default Mailbox Size (seconds):         775
Default Caller Message Size (seconds):  240
Maximum Recording Size (seconds):       900
Default Message Age (days):             30
System Capacity (minutes):              840
Default Prompt Language:                systemDefault
Operator Telephone:                     100
Maximum Broadcast Size (seconds):       300
Broadcast Message Age (days):           30
Broadcast Message MWI:                  disabled
Play Caller Id:                         enabled
Mandatory Message Expiry:               disabled
Mailbox Selection:                      last-redirect
10.1.10.1#
Thanks. Any insight greatly appreciated. 
Vincent

Answer 1

What I'm trying to accomplish is track the call volume routed to an extension. Is historical reporting the best way to accomplish this or is there another method?
Thanks.