Quarterly Hours
1987-01-01 32600000
1987-04-01 31240000
1987-07-01 26370000
1987-10-01 32250000
1988-01-01 32320000
1988-04-01 31610000
1988-07-01 26670000
1988-10-01 32370000
1989-01-01 32960000
1989-04-01 31710000
1989-07-01 27090000
1989-10-01 32300000
1990-01-01 32470000
1990-04-01 30810000
1990-07-01 26430000
1990-10-01 30810000
1991-01-01 30890000
1991-04-01 28920000
1991-07-01 23940000
1991-10-01 28540000
1992-01-01 28560000
1992-04-01 26880000
1992-07-01 22150000
1992-10-01 26730000
1993-01-01 25960000
1993-04-01 24730000
1993-07-01 21320000
1993-10-01 25380000
1994-01-01 25030000
1994-04-01 25240000
1994-07-01 21530000
1994-10-01 26950000
1995-01-01 27370000
1995-04-01 25790000
1995-07-01 22980000
1995-10-01 28270000
1996-01-01 28340000
1996-04-01 26530000
1996-07-01 22330000
1996-10-01 27770000
1997-01-01 26320000
1997-04-01 26630000
1997-07-01 22710000
1997-10-01 27860000
1998-01-01 26360000
1998-04-01 26510000
1998-07-01 22970000
1998-10-01 26590000
1999-01-01 26940000
1999-04-01 26590000
1999-07-01 22610000
1999-10-01 26780000
2000-01-01 26870000
2000-04-01 25820000
2000-07-01 22230000
2000-10-01 27090000
2001-01-01 27110000
2001-04-01 24950000
2001-07-01 21040000
2001-10-01 25510000
2002-01-01 24680000
2002-04-01 24070000
2002-07-01 20120000
2002-10-01 24490000
2003-01-01 23650000
2003-04-01 23170000
2003-07-01 19290000
2003-10-01 23690000
2004-01-01 22700000
2004-04-01 23050000
2004-07-01 19330000
2004-10-01 23680000
2005-01-01 22980000
2005-04-01 23360000
2005-07-01 18520000
2005-10-01 22980000
2006-01-01 22960000
2006-04-01 21820000
2006-07-01 19090000
2006-10-01 22990000
2007-01-01 23380000
2007-04-01 22120000
2007-07-01 18850000
2007-10-01 22890000
2008-01-01 22200000
2008-04-01 23170000
2008-07-01 18380000