Year	Percent
1991	9.229
1992	8.597
1993	8.457
1994	10.102
1995	9.279
1996	8.565
1997	7.871
1998	8.291
1999	8.298
2000	7.85
2001	8.093
2002	8.041
2003	8.384
2004	8.079
2005	7.722
2006	7.292
2007	8.298
2008	8.079
2009	7.81
2010	8.152
2011	7.733
2012	7.539
2013	7.625
2014	7.534
2015	7.306
2016	6.968
2017	7.645
2018	7.846
2019	7.041
2020	7.043
2021	7.044
2022	7.046