Year	Percent
1991	5.201
1992	4.872
1993	5.004
1994	4.978
1995	4.897
1996	4.818
1997	4.631
1998	4.252
1999	3.902
2000	3.955
2001	3.645
2002	3.628
2003	3.85
2004	4.245
2005	4.269
2006	4.253
2007	3.865
2008	3.578
2009	3.636
2010	4.108
2011	3.752
2012	3.682
2013	2.824
2014	3.043
2015	3.005
2016	3.005
2017	2.947
2018	2.89
2019	2.849
2020	2.813
2021	2.779
2022	2.749