When a case manager uploads data to the INDICA eDiscovery platform, the data will get processed. In case of (compressed) archive files (PST, zip, rar, etc.), the items will get checked and unpacked for further processing.
Depending on the type of file and how well it is compressed, the data will be unpacked from somewhere close to the source data size, and sometimes double or even triple in original size.
Case managers can see the total size in the case management panel in the user interface. The total size is a sum of the source size plus the unpacked size.