Year	Percent
1991	11.18
1992	4.401
1993	5.276
1994	5.534
1995	5.659
1996	5.879
1997	4.992
1998	6.26
1999	6.541
2000	6.348
2001	4.265
2002	4.326
2003	5.377
2004	5.448
2005	4.904
2006	4.79
2007	5.528
2008	4.96
2009	5.26
2010	5.374
2011	5.22
2012	5.176
2013	5.891
2014	5.692
2015	6.627
2016	6.652
2017	6.79
2018	6.773
2019	6.732
2020	6.724
2021	6.719
2022	6.716
