Bar charts are proportional to record count, and scaled.

Publication Year	Count	Percent
1974	1	1.7
1975	2	3.4
1976	3	5.2
1977	1	1.7
1978	2	3.4
1979	3	5.2
1980	4	6.9
1981	2	3.4
1982	5	8.6
1983	1	1.7
1984	1	1.7
1985	1	1.7
1986	0	0.0
1987	5	8.6
1988	0	0.0
1989	1	1.7
1990	4	6.9
1991	1	1.7
1992	3	5.2
1993	1	1.7
1994	2	3.4
1995	3	5.2
1996	1	1.7
1997	0	0.0
1998	0	0.0
1999	3	5.2
2000	1	1.7
2001	1	1.7
2002	2	3.4
2003	1	1.7
2004	1	1.7
2005	1	1.7
2006	1	1.7

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