Year	Hours
1989-01-01	37.850
1990-01-01	37.300
1991-01-01	37.025
1992-01-01	36.950
1993-01-01	36.950
1994-01-01	37.100
1995-01-01	36.850
1996-01-01	36.850
1997-01-01	36.825
1998-01-01	36.675
1999-01-01	36.700
2000-01-01	36.575
2001-01-01	36.525
2002-01-01	36.775
2003-01-01	36.325
2004-01-01	36.300
2005-01-01	36.875
2006-01-01	36.850
2007-01-01	36.725
2008-01-01	36.650