Year % 2000 3.3 2001 2.9 2002 3 2003 3.3 2004 3.2 2005 3.7 2006 4 2007 4 2008 4.3 2009 4.4 2014 3.5 2015 3.3 2016 3.4 2017 3.8 2019 3.5