Year % 2000 8.01117225629208 2001 7.92262174458708 2002 7.94362696356335 2003 7.99425447978586 2004 8.04574641347869 2005 7.89273432257028 2006 7.80850893918662 2007 7.75993974474322 2008 7.43811069210018 2009 6.68172793860472 2010 6.75579699011812 2011 6.60261119095194 2012 6.10254938716444 2013 5.87240535623949 2014 5.63174463786496 2015 5.41871241926295 2016 4.83773263666189 2017 4.65974512386357 2018 4.44992683560687 2019 3.95690606938588 2020 4.04956377470972