Auto serial the cell which has same value

[sanketgroup]

pls look into attached file.


AA
AA
AB
AC
AC
AC
AC
AC
AX
AX
AX
AZ
AZ
AM

then next column should have serial for each repeated value,

AA 1
AA 2
AB 1
AC 1
AC 2
AC 3
AC 4
AC 5
AX 1
AX 2
AX 3
AZ 1
AZ 2
AM 1