Year	Percent
1991	49.516
1992	50.339
1993	50.284
1994	50.439
1995	51.209
1996	49.704
1997	49.919
1998	50.11
1999	49.252
2000	50.364
2001	50.835
2002	50.971
2003	51.7
2004	51.747
2005	51.739
2006	52.081
2007	53.783
2008	55.074
2009	54.987
2010	55.622
2011	46.609
2012	48.007
2013	48.784
2014	49.494
2015	49.372
2016	50.009
2017	47.388
2018	48.249
2019	49.196
2020	50.066
2021	50.968
2022	51.995