Numbering the column based on another column

HELLO,

i HAVE A DATA THAT LOOKS LIKE THIS,

10199751
10199751
10199751
10199760
10199760
10199765
10199765
10199765
10199765
10199765
10199765
10199765
10199765
10199777
10199777
10199777
10199777
10199777
10199777
10199777
10199777
10199780
10199780
10199780
10199780
10199780
10199780
10199780
10199789
10199789
10199798
10199798


THE RESULT I WANT IS

10199751 1
10199751 2
10199751 3
10199760 1
10199760 2
10199765 1
10199765 2
10199765 3
10199765 4
10199765 5
10199765 6
10199765 7
10199765 8
10199777 1
10199777 2
10199777 3
10199777 4
10199777 5
10199777 6
10199777 7
10199777 8
10199780 1
10199780 2
10199780 3
10199780 4
10199780 5
10199780 6
10199780 7
10199789 1
10199789 2
10199798 3
10199798 4


LIKE THIS I HAVE SOME 40,000 FILES AND I NEED TO NUMBER THEM AUTOMATICALLY.......BASED ON THE "A" COLUMN................HOPE SOMEONE HELPS ME WITH A MACRO

THANKS

If the sample data is in Column A
Here is the the formula that will help you.

=COUNTIF($A$1:A1,A1)

Drag this formula down for as many rows as needed

you don't need a Macro

would you like still like a formula?

Thanks guys.........

Option Explicit
Sub NoWithNums()
 Dim Rng As Range, sRng As Range, Cls As Range, Rg0 As Range
 Dim Jj As Byte:                Dim MyAdd As String
 
 Set Rng = Range([A1], [A1].End(xlDown))
 Rng.Offset(1, 1).ClearContents
 For Each Cls In Rng.Offset(1)
    If Cls.Offset(, 1).Value = "" Then
        Jj = Jj + 1
        Cls.Offset(, 1).Value = 1
    End If
        Set Rg0 = Range(Cls.Offset(1), Rng(Rng.Rows.Count))
        Set sRng = Rg0.Find(Cls.Value, Rg0(1), xlFormulas, xlWhole, , xlPrevious)
        If Not sRng Is Nothing Then
            MyAdd = sRng.Address
            Do
                Jj = Jj + 1
                If sRng.Offset(, 1).Value = "" Then _
                    sRng.Offset(, 1).Value = Jj
                Set sRng = Rg0.FindNext(sRng)
            Loop While Not sRng Is Nothing And sRng.Address <> MyAdd
        End If
    Jj = 0
 Next Cls
End Sub