Year	Percent
1990	1.71178
1991	1.65266
1992	1.47254
1993	1.38096
1994	1.28285
1995	1.20286
1996	1.13875
1997	1.09071
1998	1.12097
1999	1.09295
2000	0.99531
2001	0.96515
2002	0.9901
2003	0.99405
2004	0.98126
2005	1.01681
2006	0.97176
2007	0.99998
2008	0.97936
2009	0.99379
2010	0.99736
2011	0.96549
2012	0.94173
2013	0.90243
2014	0.86577
2015	0.83868
2016	0.83005
2017	0.8288
2018	0.83469
2019	0.83064
2020	0.84218