Year	Percent
1990	1.98
1991	1.94
1992	1.85
1993	1.85
1994	1.61
1995	1.52
1996	1.54
1997	1.27
1998	1.26
1999	1.06
2000	1.05
2001	1.04
2002	1.1
2003	1.14
2004	1.05
2005	1.16
2006	1.06
2007	1.33
2008	1.4
2009	1.35
2010	1.53
2011	1.93
2012	2.27
2013	2.28
2014	2.46
2015	2.67
2016	2.9
2017	3.09
2018	3.05
2019	3.38