Year	Percent
1991	11.589
1992	11.573
1993	11.592
1994	11.54
1995	11.504
1996	11.614
1997	11.784
1998	11.952
1999	12.19
2000	12.263
2001	12.497
2002	12.721
2003	12.826
2004	12.939
2005	13.104
2006	13.159
2007	13.193
2008	13.358
2009	13.695
2010	13.672
2011	13.77
2012	13.872
2013	13.959
2014	14.021
2015	14.087
2016	14.238
2017	14.482
2018	14.621
2019	14.77
2020	14.922
2021	15.077
2022	15.244