Year	Percent
1991	49.411
1992	45.632
1993	43.045
1994	41.916
1995	40.944
1996	39.902
1997	41.622
1998	43.086
1999	43.467
2000	45.571
2001	46.389
2002	46.233
2003	45.803
2004	43.574
2005	43.319
2006	43.637
2007	43.162
2008	43.26
2009	48.103
2010	46.753
2011	46.311
2012	46.344
2013	46.718
2014	46.839
2015	47.232
2016	46.948
2017	46.439
2018	46.947
2019	47.258
2020	47.537
2021	47.885
2022	48.322