Year	Percent
1991	8.748
1992	8.319
1993	8.921
1994	8.854
1995	9.025
1996	10.986
1997	9.088
1998	9.014
1999	9.197
2000	11.299
2001	14.604
2002	15.002
2003	13.931
2004	13.881
2005	14.352
2006	14.533
2007	14.663
2008	15.457
2009	16.936
2010	12.986
2011	12.899
2012	13.22
2013	13.445
2014	13.777
2015	13.5
2016	13.527
2017	12.916
2018	12.836
2019	12.799
2020	12.916
2021	13.067
2022	13.171