Year	Percent of total labor force
1980	1.65
1981	2.001
1982	2.606
1983	3.426
1984	3.147
1985	2.588
1986	1.962
1987	2.084
1988	3.149
1989	4.908
1990	5.229
1991	5.469
1992	5.915
1993	5.948
1994	5.393
1995	4.906
1996	4.833
1997	4.034
1998	3.186
1999	3.172
2000	3.426
2001	3.546
2002	3.889
2003	4.494
2004	4.471
2005	4.616
2006	3.444
2007	2.539
2008	2.747
2009	3.266
2010	3.794
2011	3.364
2012	3.294
2013	3.773
2014	3.617
2015	4.531
2016	4.74
2017	4.216
2018	3.854
2019	3.7
2020	3.7
2021	3.7
2022	3.7
2023	3.7
2024	3.7