The 1976 U.S. Bicentennial state-flag pane included 50 different stamps.
The pane presented one stamp for each U.S. state and was issued on February 23, 1976. Each stamp displayed a state flag, the Bicentennial emblem, and the wording “Bicentennial Era 1776–1976.” The issue combined philately with a visual survey of the country’s state identities.
The number 50 refers to the number of states, not the number of stamps in every Bicentennial issue. The United States Postal Service produced many other commemorative stamps and souvenir sheets during the Bicentennial era. A planned second pane showing the full Declaration of Independence was abandoned after criticism that the Postal Service was issuing too many stamps.