Sub Macro1()
Dim hey As String, num As String
Set C = Cells.Find(What:="*", After:=[A1], SearchDirection:=xlPrevious)
If C Is Nothing Then
last = 1
Else
last = C.Row
End If
For x = 1 To last
num = Cells(x, 1).Value
If x < last Then
hey = hey + num + ","
Else
hey = hey + num
End If
Next
Cells(1, 2).Formula = hey
End Sub