Year	Hours Per Week
1970	38.8
1971	38.2
1972	37
1973	36.8
1974	36.8
1975	36.6
1976	36.3
1977	35.9
1978	35.7
1979	35.7
1980	35.6
1981	35.4
1982	35.6
1983	35.7
1984	36
1985	36.3
1986	36.5
1995	34.1851
1996	34.6253
1997	36.7184
1998	34.9281
1999	36.83
2000	37.1214
2001	35.0051
2002	35.3731
2003	34.5124
2004	34.9864
2005	36.1717
2006	36.0842
2007	36.0605
2008	36.0738
2009	35.6497
2010	36.2759
2011	36.1902
2012	36.0524
2013	35.9906
2014	35.8476
2015	35.7866
2016	36.1663
2017	35.935