Year	Percent
1991	47.04407
1992	47.72834
1993	48.43765
1994	48.57716
1995	48.53937
1996	48.71802
1997	48.3259
1998	48.55412
1999	52.25225
2000	52.17304
2001	52.79225
2002	53.77002
2003	54.89746
2004	54.0024
2005	54.34088
2006	55.30447
2007	53.43068
2008	51.31244
2009	49.34889
2010	48.08712
2011	48.62094
2012	47.12859
2013	47.326
2014	46.05983
2015	44.04816
2016	43.8142
2017	43.1522
2018	38.96661
2019	38.20073