Year	Percent
1991	10.83
1992	10.231
1993	11.109
1994	10.896
1995	11.33
1996	9.779
1997	9.255
1998	9.426
1999	9.159
2000	9.459
2001	7.308
2002	7.946
2003	7.913
2004	8.204
2005	8.048
2006	7.896
2007	7.273
2008	6.529
2009	8.747
2010	8.206
2011	8.586
2012	8.914
2013	8.887
2014	8.795
2015	9.815
2016	10.094
2017	10.134
2018	10.003
2019	9.882
2020	9.785
2021	9.699
2022	9.622