Year	Percent
1990	4.56
1991	4.68
1992	4.75
1993	4.78
1994	4.78
1995	4.75
1996	4.72
1997	4.74
1998	4.72
1999	4.67
2000	4.64
2001	4.63
2002	4.61
2003	4.59
2004	4.57
2005	5.74
2006	5.55
2007	5.82
2008	5.32
2009	4.11
2010	4.54
2011	3.58
2012	4.92
2013	4.13
2014	4.66
2015	4.26
2016	4.11
2017	5.14
2018	4.68
2019	6.75