起止日 各年天數 (13428)

D2:H5=INDEX(FREQUENCY(ROW(INDIRECT($B2&":"&$C2)),EOMONTH(DATE(D$1,{1,12},1),{-1,0})),2)

另解=MAX(MIN($C2,EOMONTH(DATE(D$1,12,1),0))-MAX($B2,EOMONTH(DATE(D$1,1,1),-1)+1)+1,)