Year	% of total labor force
1991	0.3477809258391954
1992	0.3331685999700148
1993	0.31924627232090125
1994	0.306137818347615
1995	0.2938395941409168
1996	0.28199188540150566
1997	0.2711173777382629
1998	0.2617588625006871
1999	0.2546146788757234
2004	0.27366274320446
2005	0.28156040181929515
2007	0.2674355673821507
2008	0.26064183463318163
2009	0.2480324541440808
2014	0.2990081898343196
2015	0.290094480291097
2016	0.28141864715977666
2017	0.2948355620171863
2018	0.285964996825259
2019	1.3764483523707782
2020	0.27152908891129507