Solution : https://service.sap.com/sap/support/notes/60113 (SAP Service marketplace login required)
Key words : 
incoming sales order statistics, additional key words fv45efep, prerequisites solution make, scheduling agreement item, scheduling agreements, delivery schedules, customer requested, quantity confirmed, calculated incorrectly, program correction
Related Notes : 
       
| 129470 | Incoming orders for component suppliers: Alternative update | 
| 109189 | SIS comp. supplier:Incoming order may be too high | 
| 81335 | Incoming order for sched. agreements not correct | 
| 60061 | Stats setup Cumulative issued/delivered quantities | 
| 53378 | Missing cumul.delivered qty - Setup of statistical data | 
| 47750 | Customer req.qnty from delivery schedules, SIS |