Year % of total labor force 1991 39.94618486145468 1992 40.42796161195493 1993 40.93651416365698 1994 41.269362564370425 1995 40.953546317938375 1996 41.27355497660975 1997 41.78371068417117 1998 41.99776354193144 1999 41.67878708549569 2000 41.55845478937024 2001 41.16908833193784 2002 40.24025580911383 2003 40.83475525748158 2004 41.426443961744944 2005 40.98261104229163 2006 41.30738264539074 2007 41.05324692293796 2008 40.79610053669105 2009 41.152237974844084 2010 40.59997807828026 2011 40.48755668824591 2012 40.75852341777051 2013 40.67292705493209 2014 40.82346402868578 2015 41.02502325076357 2016 41.233084850314185 2017 41.441270515726956 2018 42.14622010795598 2019 42.37605603053688 2020 42.39383413604172 2021 42.533910815810785 2022 42.51826705863747 2023 42.68612775095738