Is this close?
Sub SetOutline()
Dim lStart As Long
Dim lRow As Long
With Range("A1").CurrentRegion
.ClearOutline
lStart = 1
For lRow = 1 To .Rows.Count
If Not IsNumeric(Left(Cells(lRow, 1), 3)) Then
.Rows(lStart).Resize(lRow - lStart).EntireRow.Group
lStart = lRow + 1
End If
Next
End With
End Sub
Bill Manville. Excel MVP, Oxford, England. www.manville.org.uk