Year	Percent of total labor force
1980	3.354
1981	4.583
1982	6.525
1983	8.254
1984	8.09
1985	7.327
1986	6.52
1987	6.337
1988	6.247
1989	5.674
1990	5.112
1991	4.799
1992	4.865
1993	5.53
1994	6.193
1995	7.733
1996	7.099
1997	6.101
1998	4.93
1999	4.139
2000	3.66
2001	3.137
2002	3.665
2003	4.833
2004	5.665
2005	5.882
2006	5.014
2007	4.161
2008	3.663
2009	4.359
2010	4.995
2011	4.984
2012	5.832
2013	7.257
2014	7.434
2015	6.891
2016	6.024
2017	4.854
2018	3.839
2019	3.739
2020	3.639
2021	3.539
2022	3.439
2023	3.339
2024	3.239