Merjet and Troy, thank you for your help. I really
appreciate your solutions.

-----Original Message-----
Suppose the three fields are columns B-D (2-4) starting
in row2. Then the following code will put a 1 in col A
when the next row doesn't match. (It assumes duplicates
are contiguous, not scattered.)

HTH,
Merjet

Sub macro1()
Dim iRow As Integer
Dim iCt As Integer
Dim ws As Worksheet

Set ws = Sheets("Sheet1")
iRow = ws.Range("B65536").End(xlUp).Row
ws.Range("A2:A" & iRow).Clear
ws.Range("A2") = 1
For iCt = 3 To iRow
If ws.Cells(iCt, 2) < ws.Cells(iCt - 1, 2) Or _
ws.Cells(iCt, 3) < ws.Cells(iCt - 1, 3) Or _
ws.Cells(iCt, 4) < ws.Cells(iCt - 1, 4) Then
_
ws.Cells(iCt, 1) = 1
Next iCt
End Sub


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