Automation is changing requirements for U.S. mail. To be read by machines, envelope information should be typed in all caps, with no punctuation except for the hyphen in the zip-plus-four code, leaving two spaces between the city and state abbreviation and the state abbreviation and the zip. For times when all caps seem to put a strain on the eyes, try using all caps in a smaller type size.
JOHN DOE
BIOLOGY DEPARTMENT
NORTHERN MICHIGAN UNIVERSITY
1401 PRESQUE ISLE AVENUE
MARQUETTE MI 49855-5309