Year	Percent
1991	7.812
1992	8.396
1993	8.767
1994	8.752
1995	8.75
1996	8.788
1997	10.398
1998	9.142
1999	9.852
2000	10.112
2001	11.149
2002	11.706
2003	12.973
2004	13.733
2005	14.904
2006	15.898
2007	16.663
2008	16.347
2009	16.849
2010	16.891
2011	16.604
2012	16.642
2013	16.964
2014	17.499
2015	19.276
2016	20.773
2017	21.034
2018	21.156
2019	21.071
2020	21.011
2021	20.923
2022	20.793