Year	Percent
1970	0.92951
1972	0.96287
1973	0.95375
1974	0.98113
1975	0.99257
1976	1.00118
1977	1.00133
1978	1.00676
1980	1.01368
1981	1.01272
1983	1.01318
1984	1.00169
1985	1.00125
1986	1.0041
1987	1.00664
1991	0.98381
1992	0.99822
1998	1.026
1999	1.04307
2000	1.03114
2001	1.02783
2002	1.0385
2003	1.0307
2004	1.02283
2006	1.03918
2007	1.04436
2008	1.03118
2009	1.03693
2011	1.04009
2012	1.05583