Year	Percent
1990	5.77
1991	5.86
1992	6.13
1993	6.35
1994	6.72
1995	6.87
1996	7.02
1997	6.98
1998	7.18
1999	6.97
2000	6.7
2001	6.58
2002	6.48
2003	6.34
2004	6.21
2005	6.11
2006	6.01
2007	5.94
2008	5.9
2009	5.95
2010	5.91
2011	5.89
2012	5.87
2013	5.87
2014	5.88
2015	5.89
2016	5.9
2017	5.9
2018	6.31
2019	6.31