Year	Percent of total labor force
1980	0.209
1981	0.19
1982	0.428
1983	0.85
1984	1.138
1985	0.982
1986	0.832
1987	0.798
1988	0.72
1989	0.564
1990	0.501
1991	1.083
1992	2.549
1993	4.504
1994	4.723
1995	4.233
1996	4.656
1997	5.199
1998	3.856
1999	2.723
2000	1.824
2001	1.703
2002	2.546
2003	3.691
2004	3.879
2005	3.763
2006	3.332
2007	2.766
2008	2.577
2009	3.701
2010	3.516
2011	2.843
2012	2.905
2013	3.158
2014	3.044
2015	3.178
2016	3.323
2017	3.186
2018	2.628
2019	2.819
2020	2.793
2021	2.76
2022	2.779
2023	2.746
2024	2.714