Year	Percent
1991	52.522
1992	52.169
1993	51.209
1994	50.961
1995	51.808
1996	54.135
1997	55.39
1998	53.88
1999	54.684
2000	57.073
2001	56.418
2002	59.055
2003	61.759
2004	46.493
2005	49.825
2006	47.612
2007	45.493
2008	44.013
2009	40.38
2010	41.008
2011	42.13
2012	41.503
2013	40.449
2014	34.755
2015	34.415
2016	34.958
2017	34.844
2018	35.389
2019	35.459
2020	35.362
2021	35.305
2022	35.393