Please explain how you come to this conlucsion of the worst P/E? Google brings 1.30$ after tax for each 1$ invested into operations and it trades at 19.5 P/E.

Please explain how you come to this conlucsion of the worst P/E? Google brings 1.30$ after tax for each 1$ invested into operations and it trades at 19.5 P/E. This is very conservative.