Option Explicit
Sub Colorer_V02()
Dim i As Long
Application.ScreenUpdating = False
For i = Cells(Rows.Count, "A").End(xlUp).Row To 1 Step -1
If Range("A" & i).Interior.ColorIndex <> xlNone Then Range("A" & i).Offset(, 1).Interior.Color = Range("A" & i).Interior.Color
Next
Application.ScreenUpdating = True
End Sub