Year	Percent
1991	24.428
1992	24.934
1993	24.751
1994	25.682
1995	29.689
1996	33.43
1997	31.669
1998	33.718
1999	22.224
2000	21.425
2001	23.365
2002	26.968
2003	28.883
2004	32.152
2005	32.559
2006	34.17
2007	36.187
2008	36.435
2009	34.103
2010	32.626
2011	34.102
2012	33.444
2013	33.211
2014	34.565
2015	34.073
2016	34.661
2017	34.104
2018	34.378
2019	34.745
2020	34.953
2021	35.108
2022	35.225