Year	%
1987	2.7
1994	2.9
1995	2.8
1996	2.9
2000	3.1
2002	2.9
2003	3.1
2004	3
2005	3.1
2006	3.1
2007	3.3
2008	3.3
2009	3
2010	2.8
2011	2.8
2012	3
2013	2.8
2014	3.1
2015	3.1
2016	3.1
2017	3.4
2018	3.6
2019	3.5
2020	3.7
2021	3.6