Year	Percent
1991	4.545
1992	4.805
1993	4.91
1994	4.645
1995	4.676
1996	4.804
1997	4.78
1998	4.793
1999	4.792
2000	4.725
2001	4.781
2002	4.931
2003	5.255
2004	5.654
2005	6.075
2006	6.763
2007	7.344
2008	8.269
2009	8.802
2010	9.513
2011	10.444
2012	11.491
2013	12.362
2014	13.453
2015	13.841
2016	13.909
2017	14.013
2018	14.252
2019	14.43
2020	14.697
2021	14.981
2022	15.282