I own vote am getting a Runtime error 6 'overflow' message on the following code please solve it : Sub yahoo()

Dim n As Integer
Range("A:a").AutoFilter Field:=1, Criteria1:="*yahoo*"
n = Range("a:a").SpecialCells(xlCellTypeVisible).SpecialCells(xlCellTypeConstants).Count
Range("c1") = n

End Sub