Year	Percent
1990	2.45
1991	1.96
1992	2.05
1993	2.33
1994	4.02
1995	3.87
1996	3.38
1997	2.94
1998	3.05
1999	2.8
2000	2.95
2001	2.87
2002	2.76
2003	2.5
2004	2.19
2005	2.84
2006	3.29
2007	4.42
2008	4.74
2009	5.2
2010	5.13
2011	4.94
2012	4.92
2013	5.06
2014	5.23
2015	5.28
2016	5.02
2017	4.82
2018	4.92
2019	4.64