Year	Percent
1971	0.7295
1972	0.77082
1973	0.78859
1974	0.80638
1975	0.81621
1976	0.82838
1977	0.83788
1978	0.84436
1979	0.84165
1980	0.84932
1981	0.85265
1982	0.86176
1983	0.90899
1984	0.9381
1985	0.96749
1986	0.98911
1987	0.99506
1988	0.99924
1989	1.01014
1990	1.02782
1991	1.02437
1992	1.03643
1993	1.0396
1994	1.0372
1995	1.02307
1996	1.01892
1997	1.0252
1998	1.02466
1999	1.02463
2000	1.02975
2001	1.05334
2002	1.06588
2003	1.07104
2004	1.06943
2005	1.06916
2006	1.07211
2011	0.99866
2012	1.0143
2013	1.01669
2014	1.0122
2015	1.00448
2016	1.01494