Year	Percent
1990	0.95384
1991	0.92415
1992	1.04382
1993	1.01065
1994	0.84066
1995	0.70803
1996	0.69446
1997	0.61226
1998	0.53249
1999	0.51605
2000	0.61043
2001	0.66528
2002	0.64468
2003	0.67906
2004	0.58649
2005	0.48653
2007	0.45713
2008	0.44244
2009	0.42624
2010	0.41222
2011	0.39861
2012	0.38541
2013	0.37257
2014	0.35927
2015	0.34244
2016	0.32761
2017	0.30983
2018	0.29675
2019	0.28438
2020	0.27499