Year Percent of total labor force (Units) 1990 6.300 1991 11.800 1992 13.600 1993 16.400 1994 11.400 1995 13.341 1996 12.343 1997 11.246 1998 10.576 1999 13.133 2000 16.087 2001 18.242 2002 20.235 2003 19.942 2004 19.276 2005 18.052 2006 14.169 2007 9.944 2008 7.466 2009 8.514 2010 9.635 2011 9.632 2012 10.088 2013 10.328 2014 8.988 2015 7.499 2016 6.161 2017 4.888 2018 3.846 2019 3.279 2020 3.163 2021 3.373 2022 2.874 2023 2.820 2024 2.928 2025 2.986 2026 3.045 2027 3.200 2028 3.259 2029 3.317