Year	Percent
1991	34.806
1992	35.965
1993	36.319
1994	36.187
1995	37.673
1996	37.661
1997	38.538
1998	39.227
1999	39.45
2000	39.776
2001	39.466
2002	40.926
2003	42.011
2004	42.688
2005	43.307
2006	44.62
2007	45.087
2008	45.075
2009	45.288
2010	45.462
2011	45.839
2012	46.295
2013	46.734
2014	46.694
2015	46.947
2016	47.033
2017	47.101
2018	47.203
2019	47.287
2020	47.315
2021	47.33
2022	47.296