Re,
Sub regroupe()
Dim nblig As Long
Dim derlig As Long, lig As Long, lig2 As Long, ligFin As Long
Dim sh As Worksheet, sh2 As Worksheet
nblig = Application.InputBox("Regrouper par : ", Type:=1)
Set sh = Worksheets("Feuil1")
Set sh2 = Sheets.Add
lig2 = 2
derlig = sh.Cells(Rows.Count, "A").End(xlUp).Row - 1
For lig = 2 To derlig Step nblig
ligFin = Application.Min(lig + nblig - 1, derlig)
sh2.Cells(lig2, "A") = sh.Cells(lig, "A") & " à " & sh.Cells(ligFin, "A")
sh2.Cells(lig2, "C") = Application.Sum(Range(sh.Cells(lig, "C"), sh.Cells(ligFin, "C")))
lig2 = lig2 + 1
Next lig
End Sub
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