Year	Fish	Change
1971	34.7	2.9
1972	39.3	3.1
1973	32.4	-1.2
1974	31.8	-1.1
1975	32.8	-3.3
1976	38.4	3.7
1977	33.2	1.9
1978	29.7	-0.3
1979	25	-5.9
1980	21.8	-7.9
1981	20.8	-5.5
1982	19.7	-7.2
1983	20.8	-4.1
1984	21.1	-8.6
1985	21.3	-5.5
1986	24.3	-0.7
1987	27.4	-5.1
1988	24.5	-7.1
1989	25.2	-4.2
1990	25.9	0.9
1991	23	-6.1
1992	27.1	-4.1
1993	23.4	-4.8
1994	18.9	-11.3
1995	19.6	-9.3
1996	25.3	-10.7
1997	22	-1.8
1998	21	-7.4