Year % of total labor force 1991 38.245419973332304 1992 38.40916387244061 1993 38.588808694596686 1994 38.76041176826628 1995 38.92997394208537 1996 39.33087731706335 1997 39.78913991972642 1998 40.277223010699686 1999 40.54826235807 2000 40.61078160946755 2001 40.76113126992974 2002 40.95029048180667 2003 41.176429499448176 2004 41.428001916241485 2005 41.79963565420742 2006 42.20124004658043 2007 42.634723534717075 2008 43.01967269408373 2009 43.36414244370429 2010 42.83852049789685 2011 42.65213122921154 2012 45.16138746845431 2013 41.140310165766174 2014 39.79714032524609 2015 40.25158701885735 2016 40.34118406194548 2017 40.46074678238348 2018 40.60689153457659 2019 42.4906553086407 2020 43.27539523102455 2021 43.83604588631634 2022 43.3763342897798 2023 43.41987633166952