Year	Percent
1991	47.838
1992	46.004
1993	44.614
1994	45.536
1995	45.009
1996	50.639
1997	52.36
1998	56.082
1999	55.503
2000	56.483
2001	56.817
2002	57.788
2003	55.483
2004	56.438
2005	53.035
2006	53.182
2007	56.509
2008	58.319
2009	54.408
2010	52.489
2011	52.014
2012	53.72
2013	53.673
2014	52.083
2015	51.757
2016	50.13
2017	50.039
2018	50.114
2019	49.894
2020	49.506
2021	49.066
2022	48.616