Year	%
1988	6.24
1989	6.26
1990	8.25
1991	7.05
1992	7.14
1993	7.06
1994	7.05
1995	9.01
1996	8
1997	7.97
1998	7.14
1999	6.79
2000	6.19
2001	6.48
2002	6.13
2003	6
2004	5.83
2005	5.97
2006	5.94
2007	5.57
2008	5.47
2009	5.44
2010	5.6
2011	5.61
2012	5.76
2013	5.71
2014	5.71
2015	5.72
2016	5.69
2017	5.62
2018	5.6
2019	6.16
2020	4.32
2021	5.63