Year	Percent
1991	6.465
1992	6.458
1993	6.45
1994	6.171
1995	6.241
1996	5.336
1997	4.967
1998	4.999
1999	5.133
2000	5.152
2001	4.987
2002	4.966
2003	4.917
2004	4.855
2005	5.065
2006	5.023
2007	5.011
2008	5.08
2009	5.126
2010	5.128
2011	5.029
2012	4.943
2013	6.46
2014	6.438
2015	6.3
2016	6.168
2017	6.252
2018	6.17
2019	6.088
2020	6.001
2021	5.918
2022	5.838