Year % 2000 6.67002937381091 2001 6.74826368304065 2002 6.69668325768878 2003 6.63528025177348 2004 6.19584954487726 2005 5.95251706890751 2006 5.71346738449495 2007 5.49088271008791 2008 5.25844881762399 2009 5.05019709617585 2010 4.47612803473771 2011 4.34560678883282 2012 4.23558140846464 2013 4.05606623978562 2014 3.88912773527811 2015 3.72965478621152 2016 3.56781206518048 2017 3.16107286015537 2018 3.1519974970756 2019 2.99756232566374 2020 3.21741712168578