It's a Google search away. Seriously, the story of the cost of supporting public transportation. But you can have a link to the latter assertion http://www.outsidethebeltway.com/should-we-continue-to-subsi...
The inefficiency of the USPS speaks to the inefficiency of government services. They've lost $47bn over 10 years. Why? Because they have no incentive to care about their business model, because they can be apparently infinitely supplied by taxpayers.