(43) proof sets including a 1980, a 1981, (3) 1983, (3) 1984, (3) 1985, (3) 1987, (6) 1988, (3) 1989, (3) 1990, (6) 1991, (3) 1992, (2) 1993, (4) 1994 and (2) 1996