Background: Brian Douglas Wilson (born June 20, 1942) is an American musician, singer, songwriter, and record producer who co-founded the Beach Boys. After signing with Capitol Records in 1962, Wilson wrote or co-wrote more than two dozen Top 40 hits for the group. In addition to his lifelong struggles with mental illness, Wilson is known for his unorthodox approaches to pop composition and mastery of recording techniques, and he is widely acknowledged as one of the most innovative and significant songwriters of the late 20th century. The Beach Boys were formed by Brian, his brothers Carl and Dennis, their cousin Mike Love, and friend Al Jardine.
Context: Wilson spent a great deal of the two years following his father's June 1973 death secluded in the chauffeur's quarters of his home; sleeping, abusing alcohol, taking drugs (including heroin), overeating, and exhibiting self-destructive behavior. He attempted to drive his vehicle off a cliff, and at another time, demanded that he be pushed into and buried in a grave he had dug in his backyard. During this period, his voice deteriorated significantly as a result of his mass consumption of cocaine and incessant chain smoking. Wilson later said that he was preoccupied with "[doing] drugs and hanging out with Danny Hutton" (whose house became the center of Wilson's social life) during the mid-1970s. John Sebastian often showed up at Wilson's Bel Air home "to jam" and later recalled that "it wasn't all grimness." Although increasingly reclusive during the day, Wilson spent many nights at Hutton's house fraternizing with Hollywood Vampire colleagues such as Alice Cooper and Iggy Pop, who were mutually bemused by an extended Wilson-led singalong of the folk song "Shortnin' Bread"; other visitors of Hutton's home included Vampires Harry Nilsson, John Lennon, Ringo Starr, and Keith Moon. Micky Dolenz recalls taking LSD with Wilson, Lennon, and Nilsson, where Wilson "played just one note on a piano over and over again". On several occasions, Marilyn Wilson sent her friends to climb Hutton's fence and retrieve her husband.  Jimmy Webb reported Wilson's presence at an August 2, 1974 session for Nilsson's "Salmon Falls"; he kept in the back of the studio playing "Da Doo Ron Ron" haphazardly on a B3 organ. Later that month, he was photographed at Moon's 28th birthday party (held on August 28 at the Beverly Wilshire Hotel) wearing only his bathrobe. Sometime in 1974, Wilson interrupted a set by jazz musician Larry Coryell at The Troubadour by leaping onto stage and singing "Be-Bop-A-Lula", again wearing slippers and a bathrobe.  During summer 1974, the Capitol Records-era greatest hits compilation Endless Summer reached number 1 on the Billboard charts, reaffirming the relevance of the Beach Boys in the popular imagination. However, recording sessions for a new album under the supervision of Wilson and James William Guercio at Caribou Ranch and the band's studio in Santa Monica that autumn yielded only a smattering of basic tracks, including a banjo-driven arrangement of "The Battle Hymn of the Republic"; "It's O.K.", an uptempo collaboration with Mike Love; the ballad "Good Timin'"; and Dennis Wilson's "River Song". Eventually, Wilson diverted his attentions to "Child of Winter", a Christmas single co-written with Stephen Kalinich; released belatedly for the holiday market on December 23, it failed to chart.  Though still under contract to Warner Brothers, Wilson signed a sideline production deal with Bruce Johnston and Terry Melcher's Equinox Records in early 1975. Together, they founded the loose-knit supergroup known as California Music, which involved them along with L.A. musicians Gary Usher, Curt Boettcher, and a few others. This contract was nullified by the Beach Boys' management, who perceived it as an attempt by Wilson to relieve the burden of his growing drug expenses, and it was demanded that Wilson focus his efforts on the Beach Boys, even though he strongly desired to escape from the group. The idea of California Music immediately disintegrated.
Question: How long did it stay #1 on the charts?

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