Year	Percent
1991	3.897
1992	3.704
1993	3.552
1994	3.383
1995	3.196
1996	3.091
1997	2.958
1998	2.801
1999	2.705
2000	2.583
2001	3.265
2002	3.341
2003	3.256
2004	2.829
2005	2.756
2006	2.794
2007	2.502
2008	2.486
2009	1.979
2010	1.889
2011	1.678
2012	1.47
2013	1.826
2014	1.894
2015	2.39
2016	2.036
2017	1.934
2018	1.889
2019	1.839
2020	1.795
2021	1.756
2022	1.717