Bar charts are proportional to record count, and scaled.

Publication Year	Count	Percent
1967	1	2.6	.
1968	2	5.1	.
1969	0	0.0
1970	0	0.0
1971	0	0.0
1972	0	0.0
1973	0	0.0
1974	0	0.0
1975	0	0.0
1976	0	0.0
1977	0	0.0
1978	0	0.0
1979	0	0.0
1980	0	0.0
1981	0	0.0
1982	0	0.0
1983	0	0.0
1984	0	0.0
1985	0	0.0
1986	0	0.0
1987	0	0.0
1988	0	0.0
1989	0	0.0
1990	0	0.0
1991	0	0.0
1992	0	0.0
1993	0	0.0
1994	0	0.0
1995	1	2.6	.
1996	0	0.0
1997	1	2.6	.
1998	2	5.1	.
1999	1	2.6	.
2000	2	5.1	.
2001	0	0.0
2002	2	5.1	.
2003	2	5.1	.
2004	8	20.5	.
2005	4	10.3	.
2006	6	15.4	.
2007	3	7.7	.
2008	4	10.3	.

Items: 42