Year	Percent
1991	11.337
1992	11.768
1993	12.08
1994	11.692
1995	11.376
1996	12.019
1997	10.458
1998	9.482
1999	9.602
2000	10.308
2001	9.108
2002	11.906
2003	12.001
2004	11.937
2005	10.707
2006	12.005
2007	10.911
2008	10.478
2009	9.678
2010	9.576
2011	9.486
2012	8.875
2013	8.429
2014	7.92
2015	7.725
2016	7.25
2017	8.394
2018	8.458
2019	8.251
2020	8.175
2021	8.156
2022	8.123