Year % of total labor force 1991 35.10355366346729 1992 35.85489288667267 1993 36.95578660051296 1994 37.473343174507114 1995 37.87090053902232 1996 38.655019231539725 1997 39.14328195626749 1998 39.77390931278307 1999 40.40043828956168 2000 40.670521845116326 2001 40.845350907185676 2002 41.612954391429106 2003 41.840745477579134 2004 41.74122836776496 2005 42.28444346511921 2006 42.2840461822215 2007 43.016682533594505 2008 43.46959910019502 2009 44.31232268945503 2010 44.78651027877295 2011 45.098169284588955 2012 45.22264538983505 2013 45.41902500719569 2014 45.33499697586626 2015 45.231869519776815 2016 45.54976158900605 2017 45.724003495099936 2018 45.88808751883989 2019 45.92273046804754 2020 45.862404686391194 2021 46.477997773910865 2022 46.55257673035115 2023 46.7727224251714