Year	Percent
1991	7.953
1992	7.329
1993	7.362
1994	7.088
1995	5.892
1996	5.329
1997	5.433
1998	5.321
1999	4.903
2000	5.133
2001	5.133
2002	4.585
2003	4.607
2004	4.488
2005	4.553
2006	4.507
2007	4.185
2008	3.828
2009	3.904
2010	3.85
2011	3.765
2012	3.952
2013	3.945
2014	3.902
2015	3.768
2016	3.863
2017	3.94
2018	3.871
2019	3.799
2020	3.73
2021	3.667
2022	3.612