Year % of total labor force 1991 0.4362625963314182 1992 0.35946215925337144 1993 0.33879155278394896 1994 0.32608311457070155 1995 0.4166684417990732 1996 0.4137723700950776 1997 0.41539523112283155 1998 0.384354045721879 1999 0.38084911160359847 2000 0.36680512464884274 2001 0.4263268851251117 2002 0.4247379551262167 2003 0.408198632534581 2004 0.3535438394592427 2005 0.3657300671014961 2007 0.34628928229603645 2008 0.3354250560703776 2009 0.3281296235065079 2010 0.32526449742413105 2011 0.31310634982723645 2012 0.30737965915165416 2013 0.30450015185494633 2014 0.30180828429575723 2015 0.32145256580983955 2016 0.31393427527180134 2017 0.31738288314905055 2018 0.32408369817040794 2019 0.3828513790562118 2020 0.3291975091060084