Year % of total labor force 1991 3.2474594756884767 1992 2.2108994954966366 1993 2.158560881626271 1994 2.5698132602364225 1995 7.657228899164356 1996 7.4974087423069475 1997 6.9166119324960125 1998 6.770430994833809 1999 6.639098892746412 2000 6.502877435116042 2001 6.368154295791148 2002 6.235446800433342 2003 6.104607725757 2004 5.971934684626295 2005 5.835012972726516 2006 5.692845813904842 2007 5.552365695160489 2008 5.4225945643743945 2009 5.306601107603977 2010 5.199211137507657 2011 5.097328975926472 2012 5.001020735060951 2013 4.90835145925555 2014 4.817092282204744 2015 4.7291057594354085 2016 4.644431197482582 2017 4.559426827031251 2018 4.483954493592738 2019 4.402200007985386 2020 4.35767086883512