Year	Percent
1991	81.339
1992	80.687
1993	81.333
1994	81.796
1995	77.087
1996	78.517
1997	77.685
1998	77.875
1999	76.912
2000	77.828
2001	77.614
2002	76.852
2003	82.021
2004	82.537
2005	82.525
2006	83.449
2007	84.256
2008	84.734
2009	79.722
2010	77.889
2011	76.454
2012	75.865
2013	75.973
2014	77.125
2015	76.849
2016	76.677
2017	76.234
2018	76.226
2019	76.21
2020	76.189
2021	76.169
2022	76.146