Year	Percent
1991	46.866
1992	46.31
1993	45.79
1994	45.215
1995	44.865
1996	44.511
1997	44.285
1998	44.208
1999	44.217
2000	43.913
2001	44.283
2002	45.056
2003	45.936
2004	45.789
2005	45.44
2006	45.068
2007	43.765
2008	42.843
2009	41.64
2010	39.223
2011	35.103
2012	28.562
2013	29.399
2014	25.578
2015	29.627
2016	28.6
2017	28.036
2018	27.484
2019	26.89
2020	26.238
2021	25.582
2022	24.918