ComboBox to start from the last Row

Greetings ,

with this code, how can I let the combobox starts from the last record

Private Sub UserForm_Initialize()
Dim cell As Range
With Worksheets("Sheet1")
For Each cell In .Range("C2:C" & .Cells(Rows.Count, 3).End(xlUp).Row)
If Not IsEmpty(cell) Then ComboBox1.AddItem cell.Value
Next cell
End With
End Sub