Private Sub CommandButton1_Click()
    For Each Cell In Range("A1:A4")
        Value = Abs(Cell.Value)
        If Cell.Interior.ColorIndex = 3 Then
            If HAV = "False" Then
                HAV = Value
            ElseIf Value > HAV Then
                HAV = Value
            End If
        End If
        Range("A6").Value = HAV
    Next Cell
End Sub