Year	Percent
1992	4.47
1993	4
1994	5.25
1995	5.59
1996	6.4
1997	7.76
1998	8.8
1999	9.69
2000	7.3
2001	5.93
2002	4.95
2003	4.73
2004	4.81
2005	3.96
2006	3.69
2007	3.12
2008	4.05
2009	5.58
2010	4.91
2011	4.45
2012	3.28
2013	3.62
2014	3.57
2015	3.71
2016	3.69
2017	3.84
2018	3.27
2019	2.9
2020	3.54