Year	Percent
1991	12.964
1992	11.771
1993	8.53
1994	6.445
1995	8.474
1996	8.295
1997	7.952
1998	7.681
1999	7.41
2000	7.104
2001	6.865
2002	10.206
2003	10.836
2004	11.829
2005	11.826
2006	12.781
2007	13.686
2008	15.676
2009	16.29
2010	18.835
2011	20.485
2012	21.632
2013	21.898
2014	21.906
2015	21.932
2016	21.821
2017	20.763
2018	20.868
2019	21.067
2020	21.177
2021	21.481
2022	21.77