Year % 2000 2.72 2001 4.18 2002 2.98 2003 3.43 2004 3.26 2005 3.5 2006 3.18 2007 2.97 2008 2.41 2009 2.83 2010 2.88 2011 2.08 2012 1.73 2013 1.83 2014 2.39 2015 2.38 2016 2.45 2017 1.99 2018 1.92 2019 1.72 2020 1.28 2021 0.72