Year Percent 2000 5.5194 2001 6.0261 2002 6.51516 2003 7.00441 2004 7.49361 2005 7.9979 2006 8.49859 2007 8.99543 2008 9.48813 2009 9.97724 2010 10.4625 2011 10.94357 2012 11.42109 2013 11.89473 2014 12.36966 2015 12.84712 2016 13.32697 2017 13.81057 2018 14.29778 2019 14.79004 2020 15.28808 2021 15.88156 2022 16.40966