Year	Percent of total labor force
1999	3.2
2000	2.6
2001	2.5
2002	2.6
2003	2.3
2004	2.2
2005	2.1
2006	2.3
2007	2.5
2008	2.3
2009	2.1
2010	2.2
2011	2.492