The Postal Service initiated the Performing Arts Series in 1978 by issuing two commemorative stamps. It issued the Jimmy Rodgers stamp on May 24 and the George Cohen stamp on July 3. While issued only a few weeks apart, an increase in the one-ounce first class postage rate on May 29, 1978, resulted in a 13-cent Jimmy Rodgers stamps and a 15-cent George Cohen stamp.
By the time the Performing Arts Series concluded in 1991, this USPS series included twelve different stamps, all designed by Jim Sharp except the John McCormack stamp, which Jim Sharp and Ron Mercer jointly designed.
Reference: Kloetzel, James E., ed. 2009 Specialized Catalogue of United States Stamps & Covers. 87th ed. Sidney, Ohio: Scott Publishing Co., 2008.