Year	Percent
1970	0.9352
1971	0.92849
1972	0.93549
1973	0.94253
1974	0.94471
1975	0.9499
1976	0.96803
1977	0.9878
1978	0.99481
1979	1.00148
1980	0.98894
1981	1.00075
1982	1.00509
1983	1.00635
1984	1.00107
1991	0.99861
1992	1.01378
1993	1.01652
1994	1.00386
1998	0.98503
1999	0.98125
2000	0.98201
2001	0.97731
2002	0.97287
2003	0.97854
2004	0.97253
2005	0.97226
2006	0.9787
2007	0.98426
2008	0.98979
2009	0.99483
2010	1.00104
2011	0.99445
2012	1.00217
2013	1.00867
2014	0.99842
2015	0.99889
2016	1.00288