Year % of total labor force 1991 35.689324980408344 1992 35.84418815141402 1993 36.02421759655657 1994 36.2130017139636 1995 36.402749084885556 1996 36.49076514174228 1997 36.57369810790797 1998 36.65690306109539 1999 36.9905563415605 2000 37.31245063834841 2001 37.61950029770178 2002 37.88789803467337 2003 38.13897071294596 2004 38.399595952163146 2005 38.65533865195992 2006 38.90871171828907 2007 39.16282814520062 2008 39.41997863560036 2009 39.682825992196676 2010 39.95113232101408 2011 40.2559258192832 2012 40.59515455196167 2013 40.93176793434834 2014 41.26358468958465 2015 41.59363054634538 2016 41.9194913031507 2017 42.24500027135791 2018 42.574998292153495 2019 42.90673021612294 2020 42.9270393292789 2021 43.50216968974075 2022 43.23680838904859 2023 43.314399164367224