Year	Percent
1991	2.22
1992	2.31
1993	2.48
1994	3.3
1995	5.38
1996	3.98
1997	3.09
1998	2.73
1999	2.14
2000	1.79
2001	1.95
2002	2.26
2003	2.6
2004	2.95
2005	2.81
2006	2.82
2007	2.87
2008	3.09
2009	4.48
2010	4.47
2011	4.32
2012	4.07
2013	4.17
2014	4.08
2015	3.68
2016	3.35
2017	2.95
2018	2.82
2019	3.01
2020	4.13