Year	Percent
1991	52.545
1992	50.502
1993	48.663
1994	44.192
1995	44.458
1996	45.674
1997	45.158
1998	44.8
1999	43.46
2000	42.572
2001	43.052
2002	42.508
2003	43.504
2004	42.208
2005	42.429
2006	43.21
2007	44.082
2008	45.329
2009	43.746
2010	43.243
2011	43.366
2012	43.364
2013	43.653
2014	44.152
2015	45.297
2016	46.99
2017	48.043
2018	48.312
2019	48.239
2020	48.142
2021	47.998
2022	47.828