ExcelBanter - Code for new row and specific filling down

I have the following piece of code that inserts a new row
in a given position (the active cell row in current
worksheet) on each of the 8 listed worksheets below.
When the new row is inserted, the code then 'pulls down'
formulae from the above row - this is where the problem
lies, i only want certain cells to copy down from above,
eg where there is a formulae that needs to be copied down,
i do not want manual entry cells to copy actual data down
from above.
How can i specify which specific cells to copy down?

OR

Is there a method by which i can fill down - as the coding
presently does, and then clear the contents of each cell -
but leave the formulae present?

Many Thanks
Lucy

Private Sub CommandButton1_Click()

Dim wks As Worksheet

Dim l_Row As Long
Dim rng As Range

ActiveCell.Select
l_Row = ActiveCell.Row

If l_Row = ActiveSheet.Rows.Count Then
MsgBox "Can't add any more rows!"
Exit Sub
ElseIf l_Row = 1 Then
MsgBox "Can't fill down from above row 1."
Exit Sub
End If

For Each wks In ThisWorkbook.Worksheets

If wks.Name = "Year Summary 02-03" _
Or wks.Name = "Year Summary 03-04" _
Or wks.Name = "Budgeted Hours" _
Or wks.Name = "Associates Hours (actuals)" _
Or wks.Name = "Directors Hours (actuals)" _
Or wks.Name = "Invoices (actuals)" _
Or wks.Name = "Project Costs" _
Or wks.Name = ActiveSheet.Name Then

Set rng = wks.Cells(l_Row, 1).EntireRow

rng.Insert

rng.Offset(-1, 0).FillDown

End If
Next

End Sub