Year	%
1987	9.4
1992	9.8
1995	10.7
2000	10.4
2003	9.8
2004	9.9
2005	9.8
2006	9.8
2007	9.8
2008	9.8
2009	9.2
2010	9.3
2011	9.4
2012	9.3
2013	9.1
2014	9.1
2015	9.4
2016	9.2
2017	9.1
2018	9.3
2019	9.5
2020	9.4
2021	9.2