Year	Percent
1981	0.97906
1986	0.98893
1989	0.99629
1990	1.01236
1992	1.02923
1999	1.0122
2000	1.01431
2001	0.99544
2002	0.99715
2003	1.00296
2004	1.00272
2005	0.9959
2006	0.99598
2007	0.99672
2009	1.03004
2010	0.99442
2011	0.99906
2012	0.99458
2013	1.00111
2014	1.00165
2015	1.00644
2016	0.99616