Year	Percent
1990	3.63914
1991	3.52927
1992	3.4308
1993	3.34088
1994	4.05953
1995	7.09019
1996	6.94217
1997	6.67217
1998	6.43849
1999	6.00318
2000	5.82245
2001	6.19159
2002	6.63081
2003	6.44427
2004	5.86081
2005	6.2827
2006	5.01731
2007	4.9042
2008	4.79954
2009	4.83299
2010	4.73917
2011	4.65765
2012	4.61902
2013	4.58556
2014	4.55503
2015	4.5265
2016	5.88908
2017	3.87666
2018	3.76142
2019	3.67909
2020	3.66951