Question: When was the American Theater Hall of Fame founded?

Context articles: Florenz Ziegfeld Jr.
American Theater Hall of Fame
Patti LuPone
Marian Seldes
Florence Reed
Gene Saks
Elaine Stritch
John Lithgow
Kitty Carlisle
Henry Hewes

Florenz Edward Ziegfeld Jr. (March 21, 1867 – July 22, 1932), popularly known as Flo Ziegfeld, was an American Broadway impresario, notable for his series of theatrical revues, the "Ziegfeld Follies" (1907–1931), inspired by the "Folies Bergère" of Paris.
 He also produced the musical "Show Boat".
 He was known as the "glorifier of the American girl".
 Ziegfeld is a member of the American Theater Hall of Fame.
The American Theater Hall of Fame in New York City was founded in 1972.
 Earl Blackwell was the first head of the organization's Executive Committee.
 In an announcement in 1972, he said that the new "Theater Hall of Fame" would be located in the Uris Theatre (then under construction, now the Gershwin).
 James M. Nederlander and Gerard Oestreicher, who leased the theatre, donated the space for the Hall of Fame; Arnold Weissberger was another founder.
 Blackwell noted that the names of the first honorees would "be embossed in bronze-gold lettering on the theater's entrance walls flanking its grand staircase and escalator."
 The first group of inductees was announced in October 1972.
Patti Ann LuPone (born April 21, 1949) is an American actress and singer, best known for her work in stage musicals.
 She is a two-time Grammy Award winner and a two-time Tony Award winner.
 She is also a 2006 American Theater Hall of Fame inductee.
Marian Hall Seldes (August 23, 1928 – October 6, 2014) was an American stage, film, radio, and television actress whose career spanned over 60 years.
 A five-time Tony Award nominee, she won the Tony Award for Best Featured Actress in a Play for "A Delicate Balance" in 1967, and received subsequent nominations for "Father's Day" (1971), "Deathtrap" (1978–82), "Ring Round the Moon" (1999), and "Dinner at Eight" (2002).
 She also won a Drama Desk Award for "Father's Day".
 Her other Broadway credits included "Equus" (1974–77), "Ivanov" (1997), and "Deuce" (2007).
 She was inducted into the American Theater Hall of Fame in 1995 and received the Special Tony Award for Lifetime Achievement in 2010.
Florence Reed (January 10, 1883 – November 21, 1967) was an American stage and film actress.
 She is remembered for several outstanding stage productions, including "The Shanghai Gesture", "The Lullaby", "The Yellow Ticket" and "The Wanderer".
 Her best remembered movie role was as Miss Havisham in the 1934 production of "Great Expectations".
 In this version, however, Miss Havisham was changed from a completely insane woman to an eccentric, who did not wear her wedding veil constantly, and who dies peacefully rather than as a result of suffering burns in a fire.
 In the 1950s Reed performed in several early television shows, such as "The Philco Television Playhouse", "Kraft Television Theatre" and "The United States Steel Hour".
She is a member of the American Theater Hall of Fame.
Gene Saks (November 8, 1921 – March 28, 2015) was an American stage, film director, and actor.
 An inductee of the American Theater Hall of Fame, his acting career beginning with a debut on Broadway in 1949.
 As a director, he was nominated for seven Tony Awards, winning three for his direction of "I Love My Wife", "Brighton Beach Memoirs" and "Biloxi Blues".
 He also directed a number of films during his career.
 He was married to Bea Arthur, who died in 2009, from 1950 until 1980, and subsequently to Keren Saks, from 1980 to his death in 2015.
Elaine Stritch (February 2, 1925 – July 17, 2014) was an American actress and singer, known for her work on Broadway.
 She made her professional stage debut in 1944 and appeared in numerous stage plays, musicals, feature films and television series.
 She was inducted into the American Theater Hall of Fame in 1995.
John Arthur Lithgow ( ; born October 19 , 1945) is an American actor, musician, singer, comedian, voice actor, and author.
 He has received two Tony Awards, six Emmy Awards, two Golden Globe Awards, three Screen Actors Guild Awards, an American Comedy Award, four Drama Desk Awards and has also been nominated for two Academy Awards and four Grammy Awards.
 Lithgow has received a star on the Hollywood Walk of Fame and has been inducted into the American Theater Hall of Fame.
Kitty Carlisle (born Catherine Conn; also known as Kitty Carlisle Hart; September 3, 1910April 17, 2007) was an American singer, actress and spokeswoman for the arts.
 She is best remembered as a regular panelist on the television game show "To Tell the Truth".
 Carlisle served 20 years on the New York State Council on the Arts.
 In 1991, she received the National Medal of Arts from President George H. W. Bush.
 Eight years later, in 1999, she was inducted into the American Theater Hall of Fame.
Henry Hewes (April 9, 1917 – July 18, 2006) was the drama critic for the "Saturday Review" weekly literary magazine from 1955 to 1979.
 He was the first major critic to regularly review regional and international theater.
 His interest in regional theater led him to found the American Theater Critics Association, the Tony Award for regional theater, and the American Theater Wing's design awards, now called the Hewes Awards.
 In 2002, he was inducted into the American Theater Hall of Fame.