累加>=5 重算後總數 (13099)

D2=IF(SUM(C$2:C2)-SUM(D$1:D1)>=5,SUM(C$2:C2)-SUM(D$1:D1),)

F2=SUM(C:C)-SUM(D:D)

C2:C16 格式化=ROW()>LOOKUP(1,0/(D$2:D$16>=5),ROW(C$2:C$16))