Biff has seen concerts during 17 years.

Year   Concerts Seen  
2019 1 concert
2017 1 concert
2016 1 concert
2013 1 concert
2012 2 concerts
2010 1 concert
2006 1 concert
2003 1 concert
2002 1 concert
2000 2 concerts
1992 1 concert
1989 1 concert
1986 1 concert
1985 3 concerts
1984 2 concerts
1982 6 concerts
1981 1 concert