字符日起訖 找出天數 計算平均 (15136)

D2=C2/(LOOKUP(1,0/FIND("-"&ROW($1:$31)&".",B2),ROW($1:$31))-LEFT(B2,FIND("-",B2)-1)+1)

另解=C2/ROWS(INDIRECT(SUBSTITUTE(LEFT(B2,FIND(".",B2)-1),"-",":")))