Year	Percent
1991	45.732
1992	48.174
1993	53.444
1994	52.337
1995	52.997
1996	52.533
1997	53.383
1998	55.323
1999	55.309
2000	56.258
2001	56.1
2002	55.615
2003	55.824
2004	57.648
2005	57.784
2006	58.289
2007	58.296
2008	59.321
2009	60.511
2010	61.167
2011	62.319
2012	63.399
2013	64.584
2014	69.248
2015	71.44
2016	71.383
2017	71.181
2018	71.548
2019	71.912
2020	72.328
2021	72.751
2022	73.254