Year	Hours
1970-01-01	39.50000000
1971-01-01	39.47500000
1972-01-01	38.67500000
1973-01-01	38.82500000
1974-01-01	38.82500000
1975-01-01	37.97500000
1976-01-01	37.72500000
1977-01-01	37.40000000
1978-01-01	36.92500000
1979-01-01	37.80000000
1980-01-01	37.50000000
1981-01-01	37.57500000
1982-01-01	36.20000000
1983-01-01	35.62500000
1984-01-01	36.37526900
1985-01-01	37.03013375
1986-01-01	37.14604050
1987-01-01	37.42804650
1988-01-01	38.05166350
1989-01-01	37.82590725
1990-01-01	38.15132750
1991-01-01	37.63541775
1992-01-01	38.04838700
1993-01-01	38.17331025
1994-01-01	38.98633225
1995-01-01	38.78802475
1996-01-01	38.67912100
1997-01-01	38.57906900
1998-01-01	38.56740200
1999-01-01	38.90229450
2000-01-01	38.55534400
2001-01-01	38.49146925
2002-01-01	38.47697550
2003-01-01	38.39728700
2004-01-01	38.40704725
2005-01-01	38.33678775
2006-01-01	38.22700475
2007-01-01	37.93957625
2008-01-01	38.02632200