Year	Percent
1973	0.82085
1974	0.91812
1975	0.9271
1976	0.93849
1977	1.00972
1978	1.04464
1979	1.02605
1980	0.98881
1981	0.94659
1982	0.96409
1983	0.957
1984	0.94685
1985	0.94649
1986	0.96281
1987	1.0034
1988	1.02486
1989	1.03666
1990	1.03986
1991	1.03622
1992	1.03664
1993	1.03574
1994	1.01987
1995	1.00575
1997	1.03132
1998	1.04499
2016	0.95281