Year % of total labor force 1991 2.5551834451368047 1992 2.4765669143614595 1993 2.4042317437744885 1994 2.3603461841070024 1995 2.773665615749095 1996 2.7073770518132316 1997 2.648401623493534 1998 2.5905623303102856 1999 2.5216525617789003 2000 2.4825386181849414 2001 2.496834894589506 2002 2.4685708237780197 2003 2.418402006753263 2004 2.404850641460241 2005 2.363758738020287 2006 2.269081522841488 2007 2.2245717880167564 2008 2.1831718451769073 2009 2.1634594861405247 2010 2.1475129999673244 2011 2.131130413823389 2012 2.1288357909781186 2013 2.0992700211259328 2014 2.078120067318239 2015 2.0734089686156905 2016 2.0837137509678927 2017 2.103135004852599 2018 2.0609447696147987 2019 2.022769976271922 2020 2.0582672017380474