Year	% of total labor force (national estimate)
1981	2.15
1982	2.27
1987	2.4
1989	1.94
2003	2.807
2004	2.971
2006	1.902
2010	3.497
2011	4.126
2012	2.765
2013	3.017
2014	2.717
2015	2.506
2016	2.583
2017	2.462
2018	2.283
2019	2.193
2021	2.174
2022	3.051
