Year	Percent
1990	0.41308
1991	0.40649
1992	0.39766
1993	0.39169
1994	0.37869
1995	1.26574
1996	1.23729
1997	1.20867
1998	1.26676
1999	1.26835
2000	1.23974
2001	0.44227
2002	0.43309
2003	0.42199
2004	0.30148
2005	0.44169
2006	0.43552
2007	0.57905
2008	0.57378
2009	0.5853
2010	0.59784
2011	0.60035
2012	0.58432
2013	0.58293
2014	0.57206
2015	0.58115
2016	0.58358
2017	0.57312
2018	0.56821
2019	0.71932
2020	0.74302