Solution : https://service.sap.com/sap/support/notes/1597281 (SAP Service marketplace login required)
Key words :
'space -> single table analysis', uncompressed record length, compressed record length, relevant support package, average compression ratio, dba cockpit, displayed incorrectly, estimated size, compression dictionary, active dictionary
Related Notes :
| 1309424 | DB6: DBA Cockpit Correction Collection SAP Basis 7.01 / 7.11 |