Year	Percent
1991	55.283
1992	55.297
1993	53.916
1994	52.868
1995	52.241
1996	52.025
1997	52.583
1998	52.885
1999	52.724
2000	53.526
2001	54.917
2002	55.302
2003	54.627
2004	57.14
2005	51.269
2006	53.172
2007	53.181
2008	50.748
2009	51.584
2010	48.883
2011	47.805
2012	50.805
2013	44.62
2014	44.855
2015	44.309
2016	45.192
2017	45.128
2018	44.943
2019	44.724
2020	44.512
2021	44.308
2022	44.12