Year	Percent
1991	6.759
1992	4.286
1993	4.25
1994	4.004
1995	2.958
1996	3.513
1997	3.968
1998	4.566
1999	5.413
2000	6.634
2001	7.903
2002	6.264
2003	6.136
2004	7.23
2005	6.764
2006	6.838
2007	7.382
2008	7.491
2009	5.548
2010	5.532
2011	5.983
2012	5.532
2013	5.444
2014	5.488
2015	5.659
2016	5.559
2017	5.524
2018	5.494
2019	5.456
2020	5.412
2021	5.353
2022	5.288