Year % of total labor force 1991 0.2861953113109289 1992 0.22516886628009122 1993 0.219011892115203 1994 0.22422832452756006 1995 0.24306054638210378 1996 0.23648859190711088 1997 0.27641444176075586 1998 0.2691091448594155 1999 0.30376803919763984 2000 0.25425028288029716 2001 0.3731671997610056 2002 0.36362965744455034 2003 0.3545211362629929 2004 0.34460202041887583 2005 0.33817431617319926 2006 0.3316717669731491 2007 0.32330172646514604 2008 0.3151368884613056 2009 0.30712069570344974 2010 0.2991498438428582 2011 0.29110886673762054 2012 0.2848171568791888 2013 0.2787204138495761 2014 0.2721314834507018 2015 0.328079339557917 2016 0.3202340834293689 2017 0.33566343080874467 2018 0.339410082750309 2019 0.3309906910575043 2020 0.3249181759868741