Year	Percent
1991	6.769
1992	7.251
1993	7.522
1994	7.123
1995	6.377
1996	6.375
1997	6.407
1998	5.63
1999	4.688
2000	3.982
2001	3.735
2002	4.058
2003	3.746
2004	2.774
2005	2.631
2006	2.392
2007	2.248
2008	2.182
2009	2.04
2010	1.77
2011	1.433
2012	1.664
2013	1.665
2014	1.692
2015	1.325
2016	1.415
2017	1.423
2018	1.379
2019	1.332
2020	1.299
2021	1.26
2022	1.225