Year	Percent
1991	47.185
1992	45.097
1993	46.803
1994	45.295
1995	48.734
1996	52.153
1997	52.322
1998	52.404
1999	55.419
2000	50.07
2001	49.635
2002	52.414
2003	55.267
2004	49.985
2005	47.416
2006	53.101
2007	53.966
2008	53.035
2009	58.434
2010	58.725
2011	57.284
2012	57.367
2013	59.027
2014	54.917
2015	56.498
2016	54.011
2017	54.067
2018	53.873
2019	53.71
2020	53.533
2021	53.315
2022	53.096