Achived Mail File Size

[sinktip]

How big should an archive be relative to the size of the original mailbox?
I have just downloaded a 3GB inbox to Mac Mail (snowleopard).
Archived it is ~113MB. I've never done this before (Mac newb), does that seem right to you?

 

[BrianBaughn]

Are you set to download all messages and attachments in the account settings?

 

[sinktip]

All the attachments in the messages seem to have been downloaded by Mac Mail. I can open them etc.
3GB to 113MB seems like very high compression to me.