Year	Percent
1991	76.586
1992	77.876
1993	76.177
1994	76.175
1995	79.825
1996	77.196
1997	77.237
1998	77.358
1999	77.344
2000	77.28
2001	77.026
2002	80.227
2003	79.89
2004	78.93
2005	80.487
2006	79.794
2007	80.832
2008	79.793
2009	81.573
2010	80.412
2011	80.071
2012	80.37
2013	79.983
2014	79.852
2015	79.825
2016	79.807
2017	79.753
2018	79.739
2019	79.746
2020	79.779
2021	79.833
2022	79.901