Postal Service through the years

POSTED: 11:05 AM Feb 06 2013   UPDATED: 12:35 PM 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.