Solution : https://service.sap.com/sap/support/notes/815130 (SAP Service marketplace login required)
Key words : 
split valuated material, split valuation reason, split valuated materials, transaction mm03, previous month', stocks /values, stocks / values, eachvaluation type, totals record, theprevious month
Related Notes : 
       
| 834147 | MBEWH entries: Material with split valuation | 
| 827988 | RMFIFO00: Error in material with split valuation |