Year	Percent
1991	5.983
1992	5.993
1993	6.063
1994	5.468
1995	5.282
1996	5.262
1997	4.452
1998	4.523
1999	4.616
2000	4.577
2001	4.629
2002	4.722
2003	4.888
2004	5.467
2005	5.753
2006	5.767
2007	5.612
2008	5.447
2009	6.407
2010	5.112
2011	5.074
2012	4.952
2013	4.676
2014	4.497
2015	4.507
2016	4.891
2017	4.945
2018	4.814
2019	4.709
2020	4.609
2021	4.512
2022	4.429