Year	Percent
1991	59.513
1992	60.146
1993	60.354
1994	61.144
1995	58.441
1996	62.569
1997	71.055
1998	69.9
1999	71.225
2000	71.161
2001	78.794
2002	77.863
2003	80.604
2004	79.363
2005	80.639
2006	80.744
2007	81.512
2008	81.174
2009	81.306
2010	81.954
2011	81.617
2012	81.383
2013	82.053
2014	82.464
2015	82.558
2016	81.971
2017	81.686
2018	81.581
2019	81.745
2020	82.003
2021	82.357
2022	82.722