Question: What year saw the formation of the band that performed on Live at Rio ArtRock Festival '97?

full_context: Document 1: Reflexos da Noite: Reflexos da Noite (Portuguese for "Reflections of the Night") is an EP, and the first official release by the Brazilian psychedelic rock band Violeta de Outono. It came out in September 12, 1986 by now-defunct independent label Wop-Bop Records.
Document 2: Live at Rio ArtRock Festival '97: Live at Rio ArtRock Festival '97 is a live album by Brazilian psychedelic rock band Violeta de Outono, released on May 9, 2000 by Rock Symphony. It was recorded during the band's performance at the in Rio de Janeiro, in 1997.
Document 3: Eclipse (Violeta de Outono album): Eclipse is a live album by Brazilian psychedelic rock band Violeta de Outono, released in 1995 by Argentine independent label Record Runner. It was recorded during the band's performance at the SESC Pompeia in São Paulo, in 1986.
Document 4: Descendents discography: The Descendents' initial lineup of Frank Navetta (guitar), Tony Lombardo (bass guitar), and Bill Stevenson (drums) released the band's first single, "Ride the Wild" / "It's a Hectic World" in 1979. Adding singer Milo Aukerman, they next released the "Fat EP" in 1981 and their debut album "Milo Goes to College" in 1982 through SST Records. The band took a hiatus during Aukerman's collegiate studies, reconvening in 1985 for "I Don't Want to Grow Up" with guitarist Ray Cooper replacing Navetta. That same year New Alliance issued the compilation "Bonus Fat", combining the "Fat EP" with the band's first single. Doug Carrion had replaced Lombardo by 1986's "Enjoy!", but both he and Cooper soon left the band and were replaced by Karl Alvarez and Stephen Egerton, respectively.
Document 5: L.A. Style: They released a self-titled album as well as other singles, but despite massive success overseas as well as dance club play, L.A. Style's moment faded after the departure of the lead artist FX Frans Merkx and they quickly faded and dispersed in 1995. In recent years the group has again come to the attention of the pop world and rumors are that the group could be reformed with the original line up of FX as lead artist. There were also rumors that L.A. Style would be fronted by a totally new line up, however all agreed this would not go down well with the fans. Since the time of L.A. Style Wessel van Diepen continues to be one of the most sought after radio DJ's in The Netherlands and FX has been working with the main producer and old friend behind DJ Chukie, Mr. Fabian Lennsen. As FX has said, "I've worked with many great artists and even found great artists and if something comes a long that excites me then I will be back in the studio."
Document 6: Ao Vivo no Theatro Municipal: Violeta de Outono – Ao Vivo no Theatro Municipal, São Paulo, 03.05.2009 is a live video by Brazilian psychedelic rock band Violeta de Outono, released by Voiceprint Records on July 25, 2011. As the name implies, it was recorded during a show at the Theatro Municipal in São Paulo on May 3, 2009, in which they performed their 1987 debut album in its entirety, as well as some other tracks.
Document 7: Rio All-Suite Hotel and Casino: The Rio opened on January 15, 1990, as a locals casino; it had been constructed and owned and operated by Marnell Corrao Associates. The opening acts were the Brazilian Group Sérgio Mendes' 99 and Henrietta Alves of New Orleans, bringing the first two - piano act to Las Vegas, with various co-performers. A 20 - story expansion tower was added to the current Ipanema Tower in 1993. Masquerade Village, a hotel tower and casino expansion including the Masquerade Show in the Sky, opened in 1997, at a cost of over $200 million. The Rio was purchased by Harrah's Entertainment in 1999 for $888 million. After the purchase, the Culinary Workers Union organized the Rio employees through card check recognition by enforcing the neutrality clause of the existing Harrah's contract on the new acquisition.
Document 8: Mulher na Montanha: Mulher na Montanha (Portuguese for "Woman on the Mountain") is the third studio album by Brazilian psychedelic rock band Violeta de Outono. The band began work on the album in 1995, but it wouldn't be released until September 27, 1999 by Voiceprint Records, being their first of many albums to be so. It was also their first album of new material since 1989's "Em Toda Parte".
Document 9: Gustavo Rol: Upon returning to Italy, in the 1930s he became known in aristocratic and political circles. Rol engaged in various demonstrations of his supposed mystical powers, including telepathy, clairvoyance, and other psychic or magical feats. He also became a friend, among others, of film directors Federico Fellini and Franco Zeffirelli and writer Dino Buzzati. Toward the later part of his life, and after his death, Rol was a focal point of debate in Italy between skeptics and advocates of parapsychology.
Document 10: Romeo Void: Romeo Void was an American new wave/post punk band from San Francisco, California, formed in 1979. The band primarily consisted of saxophonist Benjamin Bossi, vocalist Debora Iyall, guitarist Peter Woods, and bassist Frank Zincavage. The band went through four drummers, starting with Jay Derrah and ending with Aaron Smith. The band released three albums, "It's a Condition", "Benefactor" and "Instincts", along with one EP. They are best known for the songs "Never Say Never" and "A Girl in Trouble (Is a Temporary Thing)"; the latter became a Top 40 pop single.
Document 11: Violeta de Outono: Fabio Golfetti founded Violeta de Outono in 1985 alongside Cláudio Souza; both had just parted ways with pioneering New Romantic band Zero. They would later be joined by Angelo Pastorello, and with this line-up they released a demo tape, "Memories", in the same year. The tape got the attention of independent record label Wop-Bop Records, that released their first recording, the extended play "Reflexos da Noite", in 1986.
Document 12: Vocolot: Vocolot began in 1988, when singer-songwriter Linda Hirschhorn informally assembled a group of musicians to record some of the songs she had written for four- and five-part vocal harmonies. When they had finished recording those, for the "Gather Round" album, she asked the singers to join her in an ongoing group. The founding members were Rosalind Glazer, Max Ventura, Tay Holden and Linda Hirschhorn.
Document 13: Em Toda Parte: Em Toda Parte (Portuguese for "All Around") is the second studio album by Brazilian psychedelic rock band Violeta de Outono, released in June 18, 1989 by Ariola Records. It was also their last release before they entered a hiatus period in 1993 that would last until 1995. Beginning with this album, Violeta de Outono abandons their post-punk influences and gradually shift towards a more progressive-influenced sonority.
Document 14: Seventh Brings Return: A Tribute to Syd Barrett: Seventh Brings Return: A Tribute to Syd Barrett is a live video by Brazilian psychedelic rock band Violeta de Outono, released by Voiceprint Records in 2009. It was recorded during a show at the Teatro Popular do SESI on July 17, 2006, in which they covered numerous Pink Floyd songs as a tribute to their former lead vocalist and founding member Syd Barrett, as well as a song of his 1970 solo album "The Madcap Laughs".
Document 15: Ilhas (album): Ilhas (Portuguese for "Islands") is the fourth studio album by Brazilian psychedelic rock band Violeta de Outono, released on May 9, 2005 by Voiceprint Records. It was the last album of the band to feature the original line-up of Fabio Golfetti, Cláudio Souza and Angelo Pastorello.
ground_truth: 1985
sub_queries: Live at Rio ArtRock Festival '97 >> performer Answer: Violeta de Outono
In what year did Violeta de Outono first exist? Answer: 1985