Year	Percent
1991	56.043
1992	51.574
1993	47.199
1994	47.594
1995	48
1996	46.267
1997	43.239
1998	37.694
1999	35.013
2000	34.763
2001	34.339
2002	36.339
2003	44.021
2004	33.041
2005	47.843
2006	61.766
2007	33.4
2008	51.582
2009	51.418
2010	51.322
2011	50.735
2012	47.5
2013	46.623
2014	47.656
2015	46.883
2016	43.675
2017	43.916
2018	44.594
2019	43.64
2020	42.917
2021	42.338
2022	41.685