My church uses Quickbooks 2005. They have a backup to a 512 MB thumbdrive. They have been backing up about every week for the past 18 months. The filesize of the backups have grown from 14 MB to about 23 MB.

I was planning on giving them a 1 or 2 GB thumb drive and calling it a day, but when I dumped this info into Excel and projected out the growth rate, I found that we'll hit 1 GB in July, and 10 GB in about another 18 months, and then 100 GB about 18 months after that.

It looks to me like Quickbooks saves all the transactions with every backup. Is there a way to force incremental backups? If this is the way it is, that's fine, but I'd rather not keep buying another order of magnitude of storage space every 18 months. Can I safely delete the previous backups, and just keep the recent 2 or 3 months worth?

Thanks.