A.=REPLACE(A1,1,1,2013) B.=REPLACE(A1,1,0,2013) C.=REPLACE(A1,1,2,2013) D.=REPLACE(A1,2,0,2013)
A.=MID(A1,7,4) B.=YEAR()-MID(A1,7,4) C.=YEAR(NOW())-MID(A1,7,4) D.=NOW()-MID(A1,7,4)
A.=COUNTIF(A :A ,A1)=1 B.=COUNTIF(A :A ,A1) C.COUNTIF(A :A ,A1)=1 D.=COUNT(A :A ,A1)=1