Year	Percent
1991	37.289
1992	29.061
1993	38.751
1994	51.554
1995	59.521
1996	62.568
1997	61.754
1998	56.231
1999	57.097
2000	62.238
2001	64.662
2002	64.487
2003	65.898
2004	66.276
2005	65.498
2006	68.958
2007	69.711
2008	64.245
2009	63.989
2010	61.962
2011	61.866
2012	61.383
2013	61.333
2014	60.177
2015	57.474
2016	57.567
2017	58.68
2018	58.715
2019	58.801
2020	58.959
2021	59.131
2022	59.069