Year	Percent
1991	34.762
1992	34.681
1993	33.715
1994	33.596
1995	26.033
1996	25.783
1997	25.725
1998	30.859
1999	30.491
2000	30.803
2001	29.486
2002	24.601
2003	24.153
2004	23.733
2005	30.95
2006	30.419
2007	29.991
2008	29.693
2009	29.596
2010	29.39
2011	30.439
2012	30.483
2013	27.511
2014	26.991
2015	24.477
2016	24.645
2017	24.63
2018	24.595
2019	24.547
2020	24.499
2021	24.451
2022	24.405