Year Percent 2000 42.48232 2001 42.12811 2002 41.77389 2003 41.41968 2004 41.06547 2005 42.43411 2006 43.77277 2007 45.08145 2008 46.36016 2009 47.60888 2010 48.82762 2011 50.01638 2012 51.17517 2013 52.30397 2014 53.40279 2015 54.47164 2016 55.5105 2017 56.51938 2018 57.49829 2019 58.44721 2020 59.36615 2021 60.25512 2022 61.1141