Year	Percent
1991	62.416
1992	63.099
1993	63.602
1994	63.541
1995	63.344
1996	63.573
1997	63.505
1998	63.792
1999	64.477
2000	64.798
2001	65.56
2002	66.488
2003	66.93
2004	66.984
2005	67.142
2006	66.852
2007	67.164
2008	67.884
2009	69.461
2010	69.97
2011	70.148
2012	70.551
2013	70.141
2014	69.784
2015	69.926
2016	69.953
2017	69.858
2018	69.966
2019	70.17
2020	70.297
2021	70.415
2022	70.523