Year	Percent
1991	43.531
1992	44.336
1993	44.282
1994	44.727
1995	44.551
1996	44.689
1997	44.595
1998	44.174
1999	42.62
2000	42.553
2001	42.2
2002	40.837
2003	40.542
2004	40.494
2005	41.412
2006	41.657
2007	41.279
2008	41.527
2009	40.939
2010	40.368
2011	40.12
2012	39.387
2013	40.975
2014	41.164
2015	40.82
2016	42.578
2017	42.5
2018	42.796
2019	42.797
2020	42.613
2021	42.357
2022	42.042