Year	Percent of total labor force
1990	14.2
1991	10
1992	10
1993	10
1994	10
1995	10
1996	9.085
1997	11.897
1998	13.569
1999	15.777
2000	16.046
2001	16.626
2002	12.2
2003	11.3
2004	10.3
2005	11.5
2006	11.3
2007	10.5
2008	10.4
2009	11.9
2010	13.5
2011	12.3
2012	12.1
2013	10.4
2014	10.6
2015	11
2016	12.425
2017	11.806
2018	13.871
2019	15.403
2020	16.147
2021	17.023
2022	17.842
2023	18.642
2024	19.388