Year % 2000 2.34 2001 3.03 2002 2.66 2003 2.68 2004 2.53 2005 2.92 2006 2.86 2007 2.75 2008 2.18 2009 2.38 2010 2.99 2011 2.11 2012 1.89 2013 1.84 2014 2.53 2015 2.52 2016 2.31 2017 2.12 2018 2 2019 2.1 2020 2.07 2021 0.69