Question: When was the album "So What" is on added to the National Recording Registry?

Context articles: WJSV broadcast day
Stardust (song)
So What (Miles Davis composition)
Kind of Blue
If I Could Hear My Mother Pray Again
Only Visiting This Planet
The Shape of Jazz to Come
National Recording Registry
Louis Armstrong Hot Five and Hot Seven Sessions
National Recording Preservation Board

On September 21, 1939 radio station WJSV in Washington, D.C. made an audio recording of its entire 19-hour broadcast day.
 This undertaking was a collaboration between the station and the National Archives, and it was the first time that such a comprehensive recording of a radio broadcast had been made.
 The station then donated its original set of recording discs to the National Archives, giving it a rare and complete artifact from an era frequently called the Golden Age of Radio.
 Due to their historical significance, the United States Library of Congress has since added these sound recordings to its National Recording Registry.
"Stardust" is a popular song composed in 1927 by Hoagy Carmichael with lyrics added in 1929 by Mitchell Parish.
 Carmichael first recorded the song, originally titled "Star Dust", at the Gennett Records studio in Richmond, Indiana.
 The song, "a song about a song about love", played in an idiosyncratic melody in medium tempo, became an American standard, and is one of the most recorded songs of the 20th century, with over 1,500 total recordings.
 In 2004, Carmichael's original 1927 recording of the song was one of 50 recordings chosen by the Library of Congress to be added to the National Recording Registry.
"So What" is the first track on the 1959 album "Kind of Blue" by American trumpeter Miles Davis.
Kind of Blue is a studio album by American jazz trumpeter Miles Davis.
 It is regarded by many critics as jazz's greatest record, Davis's masterpiece, and one of the best albums of all time.
 Its influence on music, including jazz, rock, and classical genres, has led writers to also deem it one of the most influential albums ever recorded.
 The album was one of fifty recordings chosen in 2002 by the Library of Congress to be added to the National Recording Registry, and in 2003 it was ranked number 12 on "Rolling Stone" magazine's list of the 500 greatest albums of all time.
"If I Could Hear My Mother Pray Again" (1922) is a popular gospel song written by John Whitfield "Whit" Vaughan (1879–1945), as a tribute to his own mother, Clara Beady Burgess-Vaughan.
 The words are based on a text by James Rowe, an English settler living in Georgia during the early twentieth century.
 A 1934 recording of the song by Thomas A. Dorsey was selected in 2007 by the United States' National Recording Preservation Board for preservation in the National Recording Registry.
Only Visiting This Planet is an album recorded by Larry Norman in 1972.
 The album was selected as the second album in CCM Magazine's "The 100 Greatest Albums in Christian Music".
 In April 2014 the album was announced as one of 25 sound recordings inducted for 2013 into the Library of Congress National Recording Registry, that preserves as "cultural, artistic and/or historical treasures, representing the richness and diversity of the American soundscape", making it the first Christian rock album chosen for the registry.
The Shape of Jazz to Come is the third album by jazz musician Ornette Coleman.
 Although Coleman initially wished for the album to be titled "Focus on Sanity", after one of the songs on the album, it was ultimately titled "The Shape of Jazz to Come" at the urging of Atlantic producer Nesuhi Ertegun, who felt that the title would give consumers "an idea about the uniqueness of the LP."
 Released on Atlantic Records in 1959, it was his debut on the label and his first album featuring his working quartet including himself, trumpeter Don Cherry, bassist Charlie Haden, and drummer Billy Higgins.
 The recording session for the album took place on May 22, 1959, at Radio Recorders in Hollywood, California.
 Two outtakes from the session, "Monk and the Nun" and "Just for You", would later be released respectively on the 1970s compilations "Twins" and "The Art of the Improvisers".
 In 2012, the Library of Congress added the album to the National Recording Registry.
The National Recording Registry is a list of sound recordings that "are culturally, historically, or aesthetically important, and/or inform or reflect life in the United States."
 The registry was established by the National Recording Preservation Act of 2000, which created the National Recording Preservation Board, whose members are appointed by the Librarian of Congress.
 The recordings preserved in the United States National Recording Registry form a registry of recordings selected yearly by the National Recording Preservation Board for preservation in the Library of Congress.
The Louis Armstrong Hot Five and Hot Seven Sessions were recorded between 1925 and 1928 by Louis Armstrong with his Hot Five and Hot Seven groups.
 According to the National Recording Registry, "Louis Armstrong was jazz's first great soloist and is among American music's most important and influential figures.
 These sessions, his solos in particular, set a standard musicians still strive to equal in their beauty and innovation."
 These recordings were added to the National Recording Registry in 2002, the first year of the institution's existence.
The United States National Recording Preservation Board selects recorded sounds for preservation in the Library of Congress' National Recording Registry.
 The National Recording Registry was initiated to maintain and preserve "sound recordings that are culturally, historically or aesthetically significant"; to be eligible, recordings must be at least ten years old.
 Members of the Board also advise the Librarian of Congress on ongoing development and implementation of the national recorded sound preservation program.