Year	Hours per Week
2001-01-01	34.7
2002-01-01	36.4
2003-01-01	36.7
2004-01-01	37.9
2005-01-01	38.7
2006-01-01	40.8
2007-01-01	38.2
2008-01-01	33.6
2009-01-01	34.6
2010-01-01	38.9
2011-01-01	39.2
2012-01-01	37.2
2013-01-01	34.5
2014-01-01	31.8
2015-01-01	35.0
2016-01-01	39.0