Question: What year did the American musician, Tim Commerford, help form Audioslave?
Context: Revelations is the third and final studio album by American rock supergroup Audioslave.  It was released on September 4, 2006 internationally and a day later in the United States, by Epic Records and Interscope Records.  The band's lead vocalist Chris Cornell departed from the band shortly after the album's release in February 2007.  Brendan O'Brien, who has produced or mixed the albums of numerous major rock acts including Rage Against the Machine, Soundgarden, Stone Temple Pilots, The Offspring, Pearl Jam, King's X, Incubus, and Bruce Springsteen, reunited with Tom Morello, Tim Commerford and Brad Wilk after producing the Rage Against the Machine albums "Evil Empire" and "The Battle of Los Angeles", and their cover of Springsteen's "The Ghost of Tom Joad".  This was also his first album with Chris Cornell after having done the mixing for the Soundgarden album Superunknown. WAKRAT is a trio composed of Tim Commerford (Rage Against the Machine/Audioslave/Prophets of Rage), Mathias Wakrat and Laurent Grangeon.  The heavily alt-punk-influenced group released their eponymous debut album in 2016. The discography of Audioslave, an American hard rock band, consists of three studio albums, two extended plays (EPs), fourteen singles, two video albums and ten music videos. Formed in Los Angeles, California in 2001, Audioslave was a supergroup featuring former Soundgarden and Temple of the Dog vocalist Chris Cornell and three former members of Rage Against the Machine – guitarist Tom Morello, bassist Tim Commerford and drummer Brad Wilk.  Signed to Epic and Interscope Records, the band released its self-titled debut album in November 2002, which peaked at number 7 on the US "Billboard" 200.  Supported by five singles, all of which reached the top ten of the "Billboard" Mainstream Rock Songs chart, "Audioslave" was certified triple platinum by the Recording Industry Association of America (RIAA).  The band's first video album, also self-titled, was released in 2003 and reached number 5 on the "Billboard" Top Music Videos chart, receiving a gold certification from the RIAA. Audioslave was an American rock supergroup formed in Los Angeles in 2001.  The four-piece band consisted of Soundgarden lead singer/rhythm guitarist Chris Cornell and Rage Against the Machine members Tom Morello (lead guitar), Tim Commerford (bass/backing vocals), and Brad Wilk (drums).  Critics first described Audioslave as a combination of Soundgarden and Rage Against the Machine, but by the band's second album, "Out of Exile", it was noted that they had established a separate identity.  Audioslave's sound was created by blending 1970s hard rock with 1990s alternative rock.  Moreover, Morello incorporated his well-known, unconventional guitar solos into the mix.  As with Rage Against the Machine, the band prided themselves on the fact that all sounds on their albums were produced using only guitar, bass, drums, and vocals. Timothy Robert Commerford (born February 26, 1968) is an American musician, best known as the bassist and backing vocalist for the American rap metal band Rage Against the Machine (1991–2000; 2007–2011), supergroups Audioslave (2001–2007) and Prophets of Rage (2016–present).  Since 2013 and 2015, he has also been the lead singer and bassist of the bands Future User and WAKRAT, respectively. This is the discography of Tom Morello, an American Grammy-award winning rock guitarist most known for his work with the bands Rage Against the Machine, Audioslave, Street Sweeper Social Club and as his folk alter-ego The Nightwatchman.  Morello started playing guitar in the mid 80's in the band Electric Sheep together with future Tool guitarist Adam Jones on bass.  After graduating "" from Harvard University in 1986 with a BA in political science, he moved to Los Angeles, where he briefly worked as an aide to Senator Alan Cranston.  Later Adam Jones moved to L.A. as well; Morello introduced Jones and Maynard James Keenan to Danny Carey, who would come to form the band Tool.  In the late 80's Morello was recruited to replace original guitar player Mike Livingston in the rock band Lock Up, in 1986 the band released its only album Something Bitchin' This Way Comes.  In 1991 Morello left Lock Up to start a new band, after being impressed by Zack de la Rocha freestyle rapping he invited him to join his band, he also drafted Brad Wilk who had previously auditioned as a drummer for Lock Up.  After Zack convinced his childhood friend Tim Commerford to join as the band's bass player the line up was complete. Prophets of Rage is an American rap rock supergroup.  Formed in 2016, the group consists of three members of Rage Against the Machine and Audioslave (bassist and backing vocalist Tim Commerford, guitarist Tom Morello, and drummer Brad Wilk), two members of Public Enemy (DJ Lord and rapper Chuck D), and rapper B-Real of Cypress Hill. Intercostal muscles are several groups of muscles that run between the ribs, and help form and move the chest wall.  The intercostal muscles are mainly involved in the mechanical aspect of breathing.  These muscles help expand and shrink the size of the chest cavity to facilitate breathing. Future User are an American rock band from Los Angeles, California formed in 2013, consisting of Rage Against the Machine and Audioslave bassist Tim Commerford, multi-instrumentalist Jordan Tarlow and drummer Jon Knox.  They describe their music as "Progtronic", combining electronic music with progressive rock.  They have released one album, "SteroidsOrHeroin", on February 24, 2015. Live at the Grand Olympic Auditorium is the second live album by the American rap metal band Rage Against the Machine, released on November 25, 2003 by Epic Records.  It is a recording of two shows Rage played at the Grand Olympic Auditorium in their hometown of Los Angeles on September 12 and 13, 2000.  The album was originally planned to be released in November 2000, but was delayed due to the break-up of the band shortly after the September concerts.  It was then slated for release a year later, but was again delayed due to the formation of Audioslave by the remaining three members of Rage (Tom Morello, Tim Commerford and Brad Wilk) with vocalist Chris Cornell.  The album was released amid mixed reviews in November 2003, mainly due to poor mixing rather than musical performance, where on the other hand the DVD version was praised by fans and critics alike.
Answer: 2001