Year	Percent
1991	43.716
1992	43.667
1993	43.596
1994	43.19
1995	43.272
1996	42.936
1997	42.745
1998	42.212
1999	41.948
2000	41.729
2001	41.861
2002	41.239
2003	41.007
2004	41.765
2005	42.798
2006	43.475
2007	44.017
2008	44.19
2009	43.34
2010	43.475
2011	44.071
2012	44.101
2013	44.153
2014	44.332
2015	44.259
2016	44.173
2017	43.944
2018	43.802
2019	43.604
2020	43.363
2021	43.184
2022	43.019