Year	Percent
1991	2.55
1992	4.31
1993	5.26
1994	5.33
1995	5.2
1996	3.6
1997	3.72
1998	3.07
1999	2.18
2000	1.94
2001	1.87
2002	2.99
2003	4
2004	4.03
2005	2.55
2006	2.83
2007	2.25
2008	2.95
2009	7.22
2010	7.56
2011	7.03
2012	6
2013	5.38
2014	4.9
2015	3.98
2016	2.98
2017	2.74
2018	2.7
2019	3.51
2020	5.48
