Why age 27 is given so much importance specially in Music industry?

Several renowned music artists died at age 27 which is also sometimes referred as the "27 Club". Often times, the cause of the death is attributed to drug and alcohol abuse or some form of violence like homicide, self harm or accidents. Jimi Hendrix, Janis Joplin, Jim Morrison, Kurt Cobain and Amy Winehouse are some of the few notable personalities in music industry who died at this age.