Postal Service through the years

POSTED: 08:05 AM PST Feb 06, 2013    UPDATED: 09:35 AM PDT May 01, 2013 
Postal Service sled

Patrick Donahoe, postmaster general of the struggling United States Postal Service, "has decided to retire" in February after serving 39 years at the agency, the USPS announced Friday. Check out landmark moments in U.S. Postal Service history.