The panes feature an unusual layout, with rows of stamps at a slight angle.
Here's a look at all the sheets from the 1900s to the 1990s.
1900s Dawn of the 20th Century
1910s America Looks Beyond Borders
1920s The Roaring Twenties
1930s Depression & New Deal
1940s World War II Transforms America
1950s Family Fun, Suburbia & Nuclear Threats
1960s Rebellious Sixties, Man on the Moon
1970s Bicentennial, Watergate & Earth Day
1980s Space Shuttle Launched, Berlin Wall Falls
1990s Cold War Ends, Economy Booms
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