Year	Percent
1991	9.347
1992	9.317
1993	9.564
1994	9.323
1995	9.216
1996	9.181
1997	9.622
1998	9.652
1999	9.156
2000	13.627
2001	19.741
2002	27.515
2003	36.785
2004	48.857
2005	51.34
2006	52.789
2007	54.052
2008	54.694
2009	55.371
2010	57.431
2011	50.246
2012	46.252
2013	41.533
2014	35.804
2015	28.759
2016	27.019
2017	21.685
2018	20.083
2019	23.548
2020	25.108
2021	25.66
2022	26.367