insert and adjust formula series below newly entered row in table

[new guy]

I am trying to figure out how to keep the formulas in series in rows in the table, after inserting new row.

right now when inserting "new user" that row keeps formatting, but does not insert a formula.

example..

=IF(C9="","",C9+1095)
=IF(C10="","",C10+1095)
=IF(C11="","",C11+1095)

How could I acomplish this by inserting code into current code?
any help is appreciated.

Option Explicit
Dim LObj As ListObject

Private Sub Removeusernow_Click()
Dim i&
i = ComboBox1.ListIndex
If i = -1 Then MsgBox "Non-existent name: remove cancelled.": Exit Sub
ComboBox1.RowSource = ""
LObj.ListRows(1 + i).Delete
ComboBox1.RowSource = LObj.Name
Unload Me
End Sub

Private Sub UserForm_Initialize()
Set LObj = Range("Tabla1").ListObject
ComboBox1.RowSource = LObj.Name
End Sub

Private Sub Addusernow_Click()
Dim i&
i = ComboBox1.ListIndex
If i > -1 Then MsgBox "Existing name: addition cancelled.": Exit Sub
ComboBox1.RowSource = ""
If ComboBox1 < LObj.Range(2, 1) Then
  LObj.ListRows.Add(1).Range(1) = ComboBox1
Else
  i = WorksheetFunction.Match(ComboBox1, LObj.ListColumns(1).DataBodyRange)
  If i < LObj.ListRows.Count Then
    LObj.ListRows.Add(1 + i).Range(1) = ComboBox1
  Else
    LObj.ListRows.Add.Range(1) = ComboBox1
  End If
End If
ComboBox1.RowSource = LObj.Name
Unload Me
End Sub

Certification.xlsm

[beyond Excel]

Hello.
What I did was convert the ListObject to a cell range and then convert it back to a ListObject.

[new guy]

sorry for the late responce, I have been trying to break down and understand list object code, i can not figure out why columbs P and R, the formulas do not get entered.

any suggestions?