Year	%
2004	3.6
2005	3.8
2006	3.7
2007	3.7
2008	3.7
2009	3.5
2010	3.6
2011	3.4
2012	3.3
2013	3.1
2014	3
2015	3.2
2016	3.4
2017	3.4
2018	3.5
2019	3.5
2020	3.5
2021	3.5