Question: What year did the band, who released a posthumous live album titled "Freedom: Atlanta Pop Festival," form?

Context articles: Freedom: Atlanta Pop Festival
Jimi Plays Monterey
Live at the Monterey Festival
Johnny B. Goode (album)
Good to Me: Live at the Whisky a Go Go, Vol. 2
Live at Monterey
The Jimi Hendrix Experience
Jeff Buckley Live À L'Olympia
Atlanta International Pop Festival (1970)
Concerto Teatro Uomo

Freedom: Atlanta Pop Festival is a posthumous live album by The Jimi Hendrix Experience, documenting their July 4, 1970 performance at the Atlanta International Pop Festival.
 Billy Cox and Mitch Mitchell accompany Hendrix.
 It features sixteen songs recorded during their evening performance, some of which appeared on the 1991 live compilation "Stages".
 However, neither album contains all the songs played, as both omit Hey Baby (New Rising Sun) with which Jimi closed the show.
 The album was released on August 28, 2015, in conjunction with the Jimi Hendrix video documentary, Jimi Hendrix: Electric Church.
Jimi Plays Monterey is a posthumous live album by Jimi Hendrix released in February 1986.
 The album documents The Jimi Hendrix Experience's performance at the Monterey Pop Festival on June 18, 1967.
 As well as songs from the band's debut album "Are You Experienced", "Monterey" also includes covers of "Killing Floor" (Howlin' Wolf), "Like a Rolling Stone" (Bob Dylan), "Rock Me Baby" (B. B. King) and "Wild Thing" (Chip Taylor).
 The version of "Wild Thing" on the album is one of the most notable live performances ever, as, in an iconic moment in rock history, he sets his guitar alight after the song and then smashes it.
Live at the Monterey Festival is a live album by the San Francisco rock band Jefferson Airplane, which was released in the United Kingdom and Europe by Thunderbolt Records in 1991.
 The album was authorized by the band and features the entire set from the group's June 17, 1967 performance at the Monterey Pop Festival.
 The album marked the first time that Jefferson Airplane's entire Monterey Pop Festival performance had been given a release by a legitimate record company.
Johnny B. Goode is a posthumous live album by Jimi Hendrix released in June 1986.
 It contains three songs from Hendrix's performance at the 1970 Atlanta International Pop Festival on July 4, 1970, and two songs from Berkeley Community Theatre on May 30, 1970.
Good To Me is a live album by American soul singer-songwriter Otis Redding, recorded at the Whisky a Go Go on Sunset Strip in Los Angeles, California in April 1966.
 The recording was made before Otis Redding attained crossover fame at the Monterey Pop Festival, and with his regular touring band.
 His other available live performances, the 1967 European Stax/Volt revue and 1967 Monterey Pop Festival are recorded with Booker T. & the M.G.'s and The Mar-Keys horns.
Live at Monterey is a posthumous live album released on October 16, 2007.
 It contains Hendrix's performance with his band, The Jimi Hendrix Experience, at the 1967 Monterey Pop Festival.
The Jimi Hendrix Experience was an American-English rock band that formed in Westminster, London, in September 1966.
 Singer, songwriter, and guitarist Jimi Hendrix, bassist and backing vocalist Noel Redding, and drummer Mitch Mitchell comprised the group, which was active until June 1969.
 During this time, they released three studio albums and became one of the most popular acts in rock.
 In April 1970, Hendrix, Mitchell, and bassist Billy Cox performed and recorded until Hendrix's death on September 18, 1970.
 This later trio was sometimes billed as the "Jimi Hendrix Experience", but the title was never formalized.
Live À L'Olympia is a live album by Jeff Buckley, released in 2001 (see 2001 in music).
 It is the second posthumous live album released since his death in 1997.
 The CD consists of performances taken from two separate concerts Buckley and his band played on July 6/7 1995 at Paris Olympia.
 The French crowd were very receptive as he was well regarded there, as shown when he was awarded France's prestigious "Grand Prix International Du Disque" earlier that year.
 Buckley paused midway in some of the songs to address the crowd and "Hallelujah" features ad-libbed lyrics in response to their enthusiasm.
 The album also features a version of a song from Nina Simone's repertoire, "That's All I Ask".
 It is one of two versions of the song officially released, the other appearing on a three-track bonus disc issued with Australian copies of Buckley's Mystery White Boy live album.
 Buckley played the song at various concerts on his 1995 European tour.
The second Atlanta International Pop Festival was a rock festival held in a soybean field adjacent to the Middle Georgia Raceway in Byron, Georgia, from July 3–5, 1970, although it did not finish until near dawn on the 6th.
 It was the only successor to the first Atlanta Pop Festival, which had been held the previous summer near Hampton, Georgia.
 The event was promoted by Alex Cooley, who had helped organize the '69 Atlanta festival as well as the '69 Texas International Pop Festival, and two years later would promote the Mar Y Sol Pop Festival in Puerto Rico from April 1–3, 1972.
Concerto Teatro Uomo is a live album by Italian Jazz fusion band Area released in 1996 and recorded in 1977 in Milan, while the band was supporting their fifth album "Maledetti (Maudits)".
 The album was criticized for its sound quality (it was not professionally recorded, unlike their 1975 live album "Are(A)zione") and for some packaging errors (the CD split between "Evaporazione" and "Arbeit Macht Frei" is wrong, there is an uncredited performance of "Diforisma Urbano" on "Il Massacro Di Brandeburgo Numero Tre in Sol Maggiore", "Improvvisazione" is "Are(a)zione" and the cover credits include Paul Lytton and Steve Lacy but they are absent in the recording ), but was also praised for its musical content (including extended improvisations) and for Demetrio Stratos' useful information about the tracks during banter between songs.
 In 2002, this album was repackaged with another posthumous live album "Parigi-Lisbona" in the boxset "Live Concerts Box".