Question: When was the band for which Bob Welch was a guitarist formed ?

Context paragraphs:
Sentimental Lady: "Sentimental Lady" is a song written by Bob Welch.  It was originally recorded for Fleetwood Mac's 1972 album "Bare Trees", but was re-recorded by Welch on his debut solo album, "French Kiss", in 1977.  It is a romantic song, originally written for Welch's first wife.  Welch recorded it again in 2003 for his album "His Fleetwood Mac Years & Beyond".

His Fleetwood Mac Years and Beyond, Vol. 2: All songs written by Bob Welch except Black Magic Woman by Peter Green, Rhiannon by Stevie Nicks, Two Sides To Beautiful by Bob Welch & Bob Mylan & World Turning by Lindsey Buckingham & Christine McVie.

Fleetwood Mac: Fleetwood Mac are a British-American rock band, formed in London in 1967.  The band have sold more than 100 million records worldwide, making them one of the world's best-selling bands of all time.  In 1998, selected members of Fleetwood Mac were inducted into the Rock and Roll Hall of Fame, and received the Brit Award for Outstanding Contribution to Music.

The Best of Bob Welch: The Best of Bob Welch is a greatest hits album released in 1991 featuring the songs of Bob Welch.

Head West: Head West is a music album released in 1970 by the American band Head West, who were based in Paris, France.  The band are best known today for their vocalist / guitarist Bob Welch, who went on to join Fleetwood Mac in 1971.  Since 1973, by which time Welch had become more well-known, the album was repackaged as more of a solo album, credited to Bob Welch with Head West.  Singles were also released but with little success.

The Other One: The Other One is the third solo album by former Fleetwood Mac guitarist Bob Welch.  The track "Future Games" was first released on the Fleetwood Mac album of the same name in 1971.  Members of Welch's backing band also make songwriting contributions here though the majority of tracks are Welch's own.

Bob Welch Looks at Bop: Bob Welch Looks At Bop is the seventh solo studio album by Bob Welch.  After a 16 year self-imposed retirement, it was his first new recording since "Eye Contact" was released in 1983.  Welch is the only musician credited on the album (except for one backing vocal by Beegie Adair), but he has stated in an interview that there were others involved by way of "modern technology".  The cover states that this is his first studio album since 1977's "French Kiss," which is not true since Welch released five follow-up albums after French Kiss.  Welch would not record another album until his 2003 recording "His Fleetwood Mac Years & Beyond".

His Fleetwood Mac Years &amp; Beyond: Bob Welch: His Fleetwood Mac Years & Beyond was an album of rerecordings of songs by former Fleetwood Mac guitarist turned solo artist Bob Welch.  As the title suggests, most of the songs were rerecordings of songs he had written and recorded both with Fleetwood Mac and solo.  The album also contained a recording of "Oh Well", a Mac hit from before Welch's time in the group, that he sang many times after Peter Green's departure; and a brand new track, "Like Rain".  The album was re-released with a different track order in 2008 as Greatest Hits & More - Revisited.

Three Hearts: Three Hearts is the second solo album by rock musician and former Fleetwood Mac guitarist Bob Welch.

French Kiss (Bob Welch album): French Kiss is the solo debut by former Fleetwood Mac singer/guitarist Bob Welch.  The songs, with the exception of "Sentimental Lady", were intended for a projected third album by Welch's previous band, Paris.  However, the group fell apart in 1977 before recording could begin.  So instead, Welch used these songs for his debut solo album.

Supporting paragraphs: Three Hearts Fleetwood Mac
Answer: 1967