Year % of total labor force 1991 0.31057058027007217 1992 0.5060267789371414 1993 0.317016293369414 1994 0.3160446381446916 1995 0.4422156774301963 1996 0.9435000707625053 1997 0.9823750720460199 1998 0.3576846701283965 1999 0.2335772166324189 2000 0.22835975796269442 2001 0.34052754527313717 2002 0.6976524531606876 2003 0.6704656280638345 2004 0.6336215173968098 2005 0.6245487035089549 2006 0.5234097384664285 2007 0.5183424915027173 2008 0.5116081565223296 2009 0.48090949603890876 2010 0.4733023658356829 2011 0.4661926005910434 2012 0.459416864361765 2013 0.4528907368747951 2014 0.3615221357877142 2015 0.35539589220884404 2016 0.3492380447599913 2017 0.36336769176729933 2018 0.33750261564527123 2019 0.34747317507088454 2020 0.34063735520073757