Year	Percent
1991	6.33
1992	5.757
1993	5.655
1994	5.294
1995	4.757
1996	4.665
1997	4.449
1998	4.264
1999	4.05
2000	4.612
2001	3.933
2002	4.216
2003	3.876
2004	3.999
2005	3.446
2006	2.88
2007	2.362
2008	2.675
2009	2.965
2010	2.492
2011	2.364
2012	1.851
2013	1.684
2014	2.065
2015	2.074
2016	1.644
2017	1.581
2018	1.531
2019	1.501
2020	1.469
2021	1.439
2022	1.413