1920s: The Roaring Twenties (Celebrate the Century Series #3), Full Sheet of 15 x 32-Cent Postage Stamps, USA 1998, Scott 3184 CELEBRATE THE CENTURY COMMEMORATIVE STAMP SERIES *USPS SET #3(1920s) *3. 1920 - THE ROARING TWENTIES The "Celebrate The Century" series by the USPS was issued in 1998. Noting various important events in the 20th century in the United States.