Quarter	Millions of US Dollars
1997-01-01	11
1997-04-01	12
1997-07-01	11
1997-10-01	10
1998-01-01	10
1998-04-01	10
1998-07-01	10
1998-10-01	12
1999-01-01	11
1999-04-01	11
1999-07-01	13
1999-10-01	13
2001-04-01	127
2001-07-01	137
2001-10-01	242
2002-01-01	240
2002-04-01	274
2002-07-01	271
2002-10-01	734
2003-01-01	750
2003-04-01	771
2003-07-01	780
2003-10-01	819
2004-01-01	803
2004-04-01	618
2004-07-01	624
2004-10-01	608
2005-01-01	592
2005-04-01	525
2005-07-01	524
2005-10-01	472
2006-01-01	479
2006-04-01	449
2006-07-01	447
2006-10-01	249
2007-01-01	251
2007-04-01	208
2007-07-01	216