Year	Percent
1962	1.27553
1963	0.99899
1964	1.14393
1965	1.3197
1966	1.26357
1967	1.31266
1968	1.16049
1969	1.1488
1970	1.18101
1971	1.50034
1972	1.69563
1973	1.13034
1974	1.33965
1975	1.17843
1976	1.11889
1977	0.79477
1978	1.09809
1979	1.12377
1980	1.16429
1981	1.09104
1982	1.14217
1983	1.11505
1984	1.02559
1985	0.99697
1986	1.05353
1987	1.2171
1988	1.24914
1989	1.33037
1990	1.33344
1991	1.37486
1992	1.40745
1993	1.42855
1994	1.09673
1996	0.84492
1997	0.79685
2003	1.39161
2004	1.51507
2005	1.46253
2006	1.50195
2007	1.59076
2008	1.52286
2009	1.73024
2010	1.55797
2011	1.38309
2012	1.50474
2013	1.3727
2014	1.52175
2015	1.77601
2016	1.72496
2017	1.28044