Year	Percent
1991	52.02
1992	52.146
1993	52.725
1994	54.108
1995	54.668
1996	54.877
1997	54.996
1998	55.762
1999	53.414
2000	51.102
2001	51.735
2002	55.844
2003	52.71
2004	45.256
2005	44.448
2006	42.746
2007	41.675
2008	35.763
2009	30.903
2010	19.447
2011	22.025
2012	25.319
2013	28.186
2014	26.688
2015	26.326
2016	26.088
2017	26.233
2018	26.025
2019	25.763
2020	25.204
2021	24.601
2022	24.063