=SOMMEPROD(SOMME.SI(INDIRECT("'S"&LIGNE(INDIRECT("$1:$"&52))&"'!A2");MOIS(1&$C$3);INDIRECT("'S"&LIGNE(INDIRECT("$1:$"&52))&"'!h"&LIGNE(DECALER('S1'!$A$4;EQUIV('Récap Jours'!$A5;'S1'!$A$5:$A$88;0);))+(COLONNES($A:A)-1))))/RECHERCHE(MOIS(1&$C$3);Mois!$A$1:$C$12)