Solution : https://service.sap.com/sap/support/notes/327964 (SAP Service marketplace login required)
Key words :
longer required history records, select folder 'structure definition', & - material valuation previous period, select object mm_matnr, archiving object mm_matnr, start transaction aobj, double-click mm_matnr, 5 navigation level 'tables, choose menu option ', archived mbew entry
Related Notes :
| 443937 | MM_MATNR: History tables not deleted |
| 320665 |