Sub PremiereCellule()
Dim ncol%, colaux As Range
Application.ScreenUpdating = False
With ActiveSheet.UsedRange
.Columns(1).Interior.ColorIndex = xlNone 'RAZ
If Application.CountA(.Columns(1)) = 0 Then Exit Sub
.Rows(1).Insert xlDown
ncol = .Columns.Count
Set colaux = .Columns(ncol + 1) 'colonne auxiliaire
colaux = "=1/(RC[-" & ncol & "]<>"""")/(R[-1]C[-" & ncol & "]="""")"
Intersect(colaux.SpecialCells(xlCellTypeFormulas, 1) _
.EntireRow, .Columns(1)).Interior.ColorIndex = 3
colaux.ClearContents
.Rows(0).Delete xlUp
End With
End Sub