Year	Percent
1991	62.487
1992	62.875
1993	64.998
1994	65.671
1995	66.507
1996	68.034
1997	72.238
1998	68.688
1999	71.126
2000	71.988
2001	73.825
2002	73.908
2003	74.35
2004	75.025
2005	75.195
2006	76.396
2007	75.828
2008	74.653
2009	76.927
2010	76.313
2011	74.834
2012	76.599
2013	77.99
2014	77.941
2015	76.61
2016	78.92
2017	78.772
2018	78.998
2019	79.214
2020	79.443
2021	79.592
2022	79.826