Question: The Jackson 5, a popular American family music group formed in 1964 but in which year did the younger band member Michael Jackson pursue a solo career while still part of the group?

full_context: Document 1: The Jackson 5 discography: This article presents the discography of The Jackson 5 (later known as The Jacksons), an American family band from Gary, Indiana. Founding group members Jackie, Tito, Jermaine, Marlon and Michael formed the group after performing in an early incarnation called The Jackson Brothers, which originally consisted of a trio of the three older brothers. Youngest brother Randy Jackson joined the group after Jermaine stayed with Motown Records and the brothers went to Epic/CBS Records. Overall, 23 of their singles rose within the "Billboard" Top 40, with the first four of them reaching #1.
Document 2: Gold (The Jackson 5 album): Gold is a compilation album of songs by The Jackson 5, an American popular music family group from Gary, Indiana. The founding members were Jackie, Tito, Jermaine, Marlon and Michael. This album features selections from their nine official studio albums during their Motown years. From their 1969 debut album "Diana Ross Presents The Jackson 5" to the last album they recorded together with Motown, 1975's "Moving Violation". The album also includes five new Motown tracks never released before.
Document 3: The Jackson 5: The Jackson 5, or Jackson Five, currently known as The Jacksons, is a popular American family music group. Formed in 1964 under the name the Jackson Brothers, the founding members were elder brothers Jackie, Tito and Jermaine. Younger brothers Marlon and Michael would join soon after. They participated in talent shows and performed in clubs on the Chitlin' Circuit. They entered the professional music scene in 1967. Signing with Steeltown Records and releasing two singles with the Steeltown label. In 1969, the group left Steeltown Records and signed with Motown.
Document 4: Victory Tour (The Jacksons tour): The Victory Tour was a concert tour of the United States and Canada by Michael Jackson and The Jackson family between July and December 1984. It was the first and only tour with all six Jackson brothers (even though Jackie was injured for most of the tour). The group performed 55 concerts to an audience of approximately 2 million. Most came to see Michael, whose album "Thriller" was dominating the popular music world at the time. Many consider it to be his "Thriller" tour, with most of the songs on the set list coming off of his "Off the Wall" album and from the "Thriller" album. The tour reportedly grossed approximately $75 million (US$ in 2016 dollars ) and set a new record for the highest grossing tour. It showcased Michael's single decorated glove, black sequined jacket and moonwalk.
Document 5: Beat It: "Beat It" is a song written and performed by American singer Michael Jackson single from the singer's sixth solo album, "Thriller" (1982). The song was produced by Quincy Jones together with Jackson. Following the successful chart performances of the "Thriller" singles "The Girl Is Mine" and "Billie Jean", "Beat It" was released on February 14, 1983 as the album's third single. The song is also notable for its famous video, which featured Jackson bringing two gangs together through the power of music and dance.
Document 6: Jackson family: The Jackson family is an American family of singers who originated in Gary, Indiana. Performing as members of The Jackson 5 and as solo artists, the children of Joseph Walter and Katherine Esther Jackson were very successful in the field of popular music from the late 1960s onwards. As a group, the eldest sons Jackie, Tito, Jermaine, Marlon, Randy and Michael, made the family's reputation, facilitating the subsequent success of siblings Rebbie, La Toya, and Janet. The Jackson 5 became known as the "First Family of Soul" (a title first held by the Five Stairsteps). The continued success of Michael and Janet's careers as solo artists led the Jacksons to become known as the "Royal Family of Pop". All nine of the Jackson siblings have gold records to their credits with La Toya holding the distinction of being the first Jackson sister to attain one (awarded by France's SNEP for "Reggae Night", a song she co-wrote for Jimmy Cliff).
Document 7: List of The Jackson 5 band members: The band member history of American R&B and pop group The Jackson 5 shows how the band has comprised different members of the Jackson family at various times during its chronology, with differing names as The Jackson Brothers (1964–1965), The Jackson 5 (1965–1975, with Motown) and The Jacksons (1975–1989, with CBS).
Document 8: Michael Jackson videography: American entertainer Michael Jackson (1958–2009) debuted on the professional music scene at age five as a member of The Jackson 5 and began a solo career in 1971 while still part of the group. Jackson has been called the King of Music Videos. Steve Huey of AllMusic observed how Jackson transformed the music video into an art form and a promotional tool through complex story lines, dance routines, special effects and famous cameo appearances, simultaneously breaking down racial barriers. Before "Thriller", Jackson struggled to receive coverage on MTV, allegedly because he was African American. Pressure from CBS Records persuaded MTV to start showing "Billie Jean" and later "Beat It", leading to a lengthy partnership with Jackson, also helping other black music artists gain recognition. MTV employees deny any racism in their coverage, or pressure to change their stance. MTV maintains that they played rock music, regardless of race. The popularity of his videos on MTV helped to put the relatively young channel "on the map"; MTV's focus shifted in favor of pop and R&B. His performance on "Motown 25: Yesterday, Today, Forever" changed the scope of live stage show; "That Jackson lip-synced 'Billie Jean' is, in itself, not extraordinary, but the fact that it did not change the impact of the performance is extraordinary; whether the performance was live or lip-synced made no difference to the audience" thus creating an era in which artists re-create the spectacle of music video imagery on stage. Short films like "Thriller" largely remained unique to Jackson, while the group dance sequence in "Beat It" has frequently been imitated. The choreography in "Thriller" has become a part of global pop culture, replicated everywhere from Indian films to prisons in the Philippines. The "Thriller" short film marked an increase in scale for music videos, and has been named the most successful music video ever by the "Guinness World Records".
Document 9: Gordon Keith (producer): Gordon Keith (1939-), was the first person to sign a recording contract with the Jackson 5 and release their records.In 1966, he and four friends founded Steeltown Records in Gary, Indiana, with each able to manage, record, and sign local talent themselves in and around Gary. The quality of the music and dance scene was high in and near Gary. Vivian Carter, founder of VeeJay Records, and The Spaniels, a prominent Doo-wop group, are examples of Gary's musical culture. Keith states that each Steeltown partner individually discovered, signed, and took the responsibility and any profit for each signed individual or group, using Steeltown Records (Steeltown label) as an umbrella to promote name recognition. Keith points out that he had himself went solo as a vocalist in the 1960s because he wearied of the lack of discipline and commitment of so many of the young singers he sang doo-wop songs with. Therefore, he was looking not only for talent, but talent with a disciplined professional attitude and commitment.
Document 10: Michael Jackson: 30th Anniversary Celebration: The Michael Jackson: 30th Anniversary Celebration was a 2001 New York City revue show by Michael Jackson. It took place on September 7, 2001 and September 10, 2001. In late November 2001, the CBS television network aired the concerts as a two-hour special in honor of Michael Jackson's thirtieth year as a solo entertainer (his first solo single, "Got to Be There", was recorded in 1971). The show was edited from footage of two separate concerts Michael had orchestrated in New York City's Madison Square Garden on September 7 and September 10 of 2001. The shows sold out in five hours. Ticket prices were pop's most expensive ever; the best seats cost $10,000 and included a dinner with Michael Jackson and a signed poster. The show was choreographed by Glenn Douglas Packard & Brian Thomas, they were nominated for a Emmy Award for Outstanding Choreography. The show was presented by David Gest, World Events LLC and Clear Channel Entertainment in conjunction with American Airlines, American Eagle and Amazon.com. Jackson reportedly earned $7.5 million for each of the two concerts. The concert official Boxscore was $10,072,105 for both concerts.
Document 11: Justin Timberlake videography: American entertainer Justin Timberlake has released four video albums and has been featured in thirty-seven music videos, seventeen films, fifteen television shows, and six commercials. He achieved early fame when he appeared in the Disney Channel television series "The New Mickey Mouse Club", alongside singers Britney Spears and Christina Aguilera and actor Ryan Gosling. Timberlake rose to fame in the late 1990s as the lead singer of the boy band NSYNC. In 2002, he launched his solo career and released his solo debut single "Like I Love You", the music video for which was directed by Bucky Chrome. Francis Lawrence directed the video for "Cry Me a River". The video features Timberlake's character as he spies on a former lover, who according to the director portrays his former romantic interest Spears. At the 2003 MTV Video Music Awards, the video won the accolades for Best Male Video and Best Pop Video.
Document 12: Billie Jean: "Billie Jean" is a song by American singer Michael Jackson. It is the second single from the singer's sixth studio album, "Thriller" (1982). It was written and composed by Jackson and produced by Jackson and Quincy Jones. There are contradictory claims on the meaning of the song's lyrics. One suggests that they are derived from a real-life experience, in which a female fan claimed that Jackson (or one of his brothers) had fathered her twins. However, Michael Jackson stated that "Billie Jean" was based on groupies he had encountered. The song is well known for its distinctive bassline played by Louis Johnson, the standard drum beat heard in the beginning, the repetition of "Billie Jean is not my lover" towards the end of the song and Michael Jackson's vocal hiccups. The song was mixed 91 times by audio engineer Bruce Swedien before it was finalized, though he reportedly went with the second mix as the final product.
Document 13: Michael Jackson: Michael Joseph Jackson (August 29, 1958 – June 25, 2009) was an American singer, songwriter, and dancer. Dubbed the "King of Pop", he was one of the most popular entertainers in the world, and was the best-selling music artist at the time of his death. Jackson's contributions to music, dance, and fashion along with his publicized personal life made him a global figure in popular culture for over four decades.
Document 14: List of songs recorded by The Jackson 5: The Jackson 5 was an American music group, formed in 1963 by the Jackson family brothers Jackie, Jermaine, Marlon, Michael and Tito. The quintet's first singles were recorded at Steeltown Records, a local label in their hometown of Gary, Indiana. Songs recorded at Steeltown included "You've Changed", "We Don't Have To Be Over 21 (to Fall in Love)" and "Big Boy". According to music journalist Nelson George, Michael Jackson and The Jackson 5's "real" recording history did not begin until their move to Motown Records in 1968. The then Detroit-based company, led by Berry Gordy, housed established recording artists such as Stevie Wonder, Marvin Gaye and Diana Ross, as well as a producing-writing team known as "The Corporation". Jackson 5 hit singles such as "I Want You Back", "ABC" and "The Love You Save" were written by the Motown team, and aided the five brothers in becoming the first black teen idols.
Document 15: Diana Ross Presents The Jackson 5: Diana Ross Presents The Jackson 5 is the debut studio album from Gary, Indiana-based soul family band the Jackson 5, released on the Motown label in December 1969. The Jackson 5's lead singer, a preteenage boy named Michael (who later became a universally-recognized pop star on his own and "The King of Pop"), and his older brothers Jackie, Tito, Jermaine, and Marlon, became pop successes within months of this album's release. "Diana Ross Presents the Jackson 5's" only single, "I Want You Back", became a number-one hit on the "Billboard" Hot 100 within weeks of the album's release and eventually sold five million copies worldwide. The album reached #5 on the Pop Albums chart, and spent nine weeks at #1 on the R&B/Black Albums chart.
ground_truth: 1971