Year	% of total labor force (national estimate)
1989	0.56
1990	0.637
1991	1.468
1992	3.681
1993	6.544
1994	7.561
1995	9.659
1996	9.915
1997	10.369
1998	9.51
1999	11.573
2000	13.36
2001	13.135
2002	10.026
2003	11.288
2004	10.248
2005	8.033
2006	5.915
2007	4.592
2008	5.455
2009	13.548
2010	16.707
2011	12.328
2012	10.021
2013	8.631
2014	7.352
2015	6.412
2016	6.882
2017	5.807
2018	5.412
2019	4.514
2020	6.956
2021	6.178
2022	5.571
2023	6.378