Year	% of total labor force (national estimate)
1991	3.0682566772844857
1992	3.276261919777861
1993	3.504896730258471
1994	3.6886152490646125
1995	4.288233858015752
1996	4.393111044476381
1997	4.530165945423939
1998	4.997798055745499
1999	5.293986301854555
2000	5.4301541680874985
2001	5.607605111311859
2002	6.182103816894969
2003	6.052932550397927
2004	5.954577402287144
2005	5.926215302054874
2006	5.6211202636133955
2007	5.621913476596407
2008	5.522713013512662
2009	5.858574906960391
2010	5.348989620826293
2011	5.3198007000037215
2012	5.252676347680613
2013	5.123791268193854
2014	5.178709508891761
2017	5.568806399399911
2018	6.1174412966459295
2019	6.237789944333945
2020	6.918302222283789
2021	6.542789315791675