Year % 1979 6.7 1986 6.5 1992 6.9 1997 6.1 2001 5.9 2002 5.5 2003 5.2 2004 4.8 2005 4.8 2006 4.8 2007 5 2008 4.8 2009 4.6 2010 4.7 2011 4.8 2012 4.8 2013 5.1 2014 5 2015 5 2016 5.1 2017 5.1 2018 5.2 2019 5.2 2020 5.4 2021 5.5