Year	Percent
1991	60.866
1992	62.116
1993	57.54
1994	57.047
1995	53.47
1996	51.604
1997	51.491
1998	50.083
1999	46.973
2000	47.554
2001	43.691
2002	44.064
2003	42.584
2004	40.426
2005	40.721
2006	40.68
2007	39.996
2008	40.361
2009	36.549
2010	36.057
2011	39.207
2012	40.372
2013	37.214
2014	31.162
2015	29.822
2016	30.824
2017	30.261
2018	29.38
2019	28.512
2020	27.667
2021	26.837
2022	26.054