Two concert posters for a concert by Bob Marley and the Wailers show the same typography and venue, yet the concerts are from different tours.
The 1977 poster was made for an Exodus Tour concert in the Paramount Northwest Theatre in Portland, Oregon on July 24 (the theatre closed down in 1984). According to Wikipedia, a toe injury of Bob Marley forced the United States concerts for this tour to be canceled – the concert advertised on the poster never happened. In the summer of 1978, Marley visited North America during his Kaya tour. This time, the canceled concert was finally performed, and recorded.
Two weights of ITC Korinna are used for the main information – tightly spaced in 1977, loosely spaced in 1978. Maybe due to the rescheduling of the concert, the date on the 1977 poster uses Clarendon. The bottom half of the poster was set in Univers in 1977, Helvetica was used the next year.