Welcome to VBAX

[vba]
Option Explicit
Sub Test()
Dim Rng As Long
Dim Cel As Range

On Error Resume Next
Rng = Worksheets("NovusDR").Range("AE7")
For Each Cel In Range("Z7").Resize(Rng)
Select Case Len(Cel)
Case 5
Cel.NumberFormat = "m/d/yyyy"
Case 1
Cel.NumberFormat = "0"
End Select
Next
End Sub

[/vba]