Year	Percent
1991	47.262
1992	46.811
1993	46.581
1994	47.743
1995	49.312
1996	49.414
1997	49.34
1998	49.802
1999	50.173
2000	51.316
2001	51.638
2002	51.988
2003	52.701
2004	52.714
2005	54.073
2006	54.779
2007	55.414
2008	55.987
2009	55.644
2010	55.548
2011	55.826
2012	55.696
2013	55.413
2014	55.031
2015	55.472
2016	55.813
2017	55.855
2018	55.881
2019	55.8
2020	55.793
2021	55.767
2022	55.727