CloudAlly is a backup service, so we only take the latest changed version of a file, in backing up Dropbox.com.
This means that there is only one automatic backup a day. Although Dropbox supports file versioning, CloudAlly only takes the latest version each day. This is to prevent storage requirements increasingly sharply.
Therefore, you will often see a discrepancy between the amount of storage Dropbox reports and the amount that CloudAlly reports. Depending on how many versions are kept and how large the files are, the difference in storage size can be large.