Background: Bruce Randall Hornsby (born November 23, 1954) is an American singer and pianist. Hornsby draws frequently from classical, jazz, bluegrass, folk, Motown, gospel, rock, blues, and jam band musical traditions. Hornsby's recordings have been recognized on a number of occasions with industry awards, including the 1987 Grammy Award for Best New Artist with Bruce Hornsby and the Range, the 1990 Grammy Award for Best Bluegrass Album, and the 1994 Grammy Award for Best Pop Instrumental Performance. Hornsby has also achieved recognition for his solo albums and performances, his touring band Bruce Hornsby and the Noisemakers, his bluegrass project with Ricky Skaggs and his appearances as a session and guest musician.
Context: Bruce Randall Hornsby was born in Williamsburg, Virginia, a son of Robert Stanley Hornsby (1920-1998), an attorney, real-estate developer and former musician, and his wife, nee Lois Saunier. Raised a Christian Scientist, he has two siblings: Robert Saunier "Bobby" Hornsby, a realtor with Hornsby Realty and locally known musician, and Jonathan Bigelow Hornsby, an engineer who has collaborated in songwriting.  He graduated from James Blair High School in Williamsburg, Virginia, in 1973, where he played on the basketball team. He studied music at the University of Richmond, as well as Berklee College of Music and the University of Miami, from which he graduated in 1977.  In the spring of 1974 Hornsby's older brother Bobby, who attended the University of Virginia, formed the band "Bobby Hi-Test and the Octane Kids" to play fraternity parties, featuring Bruce on Fender Rhodes and vocals. The band, which is listed in Skeleton Key: A Dictionary for Deadheads, performed covers of Allman Brothers Band, The Band, and predominantly Grateful Dead songs. Although Hornsby's collaboration with Bobby Hornsby would be relatively short-lived, Bobby's son R.S. was a recurring guest-guitarist with Hornsby's band and periodically toured with his uncle. His performances were often looked forward to by fans. R.S. Hornsby died on January 15, 2009 in a car accident near Crozet, Virginia. He was 28.  Following his graduation from the University of Miami, in 1977, Hornsby returned to his hometown of Williamsburg, and played in local clubs and hotel bars. In 1980, he and his younger brother (and songwriting partner) John Hornsby moved to Los Angeles, where they spent three years writing for 20th Century Fox. Before moving back to his native southeastern Virginia, he also spent time in Los Angeles as a session musician. In 1982 Hornsby joined the band Ambrosia for their last album Road Island and can be seen in the band's video for the album's single "How Can You Love Me." After Ambrosia disbanded, he and bassist Joe Puerta performed as members of the touring band for pop star Sheena Easton. Hornsby can clearly be seen in the music video for Easton's 1984 hit single "Strut."
Question: When year did Bruce Hornsby started playing with the band Grateful Dead ?. Whats the answer?