Solution : https://service.sap.com/sap/support/notes/930799 (SAP Service marketplace login required)
Key words : 
terms transaction faglb03 reason, create table type fagl_tt_period_block_rpmax, create structure fagl_periods, create structure fagl_s_period_block_rpmax, line type fagl_s_period_block_rpmax, component type periode, component type rpmax, component type, structure fagl_header, balance display
Related Notes : 
       
| 1062329 | FAGLB03: 'Month' in ledger with more than 16 periods | 
| 1047254 | FAGLB03: Drilldown using 'Total' incorrect with periods < 12 | 
| 672255 | Shortened fiscal year/changing fiscal periods |