Year % of total labor force 1991 37.99572640862056 1992 38.140339593947736 1993 38.285972004582504 1994 38.42382960530151 1995 38.48142200847375 1996 38.55528275533787 1997 38.49471066097199 1998 38.42587597847065 1999 38.36293343529657 2000 38.3474558082434 2001 38.36093804690235 2002 38.367754025807976 2003 38.3244848254492 2004 38.280394086842705 2005 38.31701807724235 2006 38.71736370612251 2007 39.12966974821796 2008 39.56184186173373 2009 40.03386849516928 2010 40.49014948060053 2011 40.936015049395046 2012 40.94605585702376 2013 40.95879439327084 2014 40.98779306075207 2015 40.75428020469892 2016 40.50972376104372 2017 40.643771319000734 2018 40.776099696059056 2019 40.87662419898179 2020 41.019057786421726 2021 41.22964497262475 2022 41.0902688197729 2023 41.20123706735414