Year % of total labor force 1991 3.6825557989403443 1992 3.536418479554765 1993 3.411079551857241 1994 3.2614437363099444 1995 3.6477102682208695 1996 3.46860908775581 1997 9.026250161001933 1998 8.774791215874934 1999 8.623840010138968 2000 7.819011008796271 2001 6.958888955950458 2002 7.07214216449045 2003 7.691357839056515 2004 7.383088789025777 2005 7.16736659363392 2006 6.803704963649067 2007 6.5311703035899145 2008 6.037848269957619 2009 5.113692109971769 2010 4.931625931993714 2011 4.80198325812612 2012 4.634113796378421 2013 4.549273626479978 2014 4.42030910418962 2015 4.293776961559351 2016 4.2412172178477086 2017 2.3314867574430553 2018 1.699588267540543 2019 1.6726006189756257 2020 1.680051073552636