Quarter	Billions of US Dollars
1997-04-01	0.025680
1998-01-01	0.025470
1999-07-01	-0.025481
2000-07-01	0.016260
2001-01-01	-0.024246
2002-07-01	-0.016565
2003-07-01	0.008780
2007-07-01	-0.003764
2008-07-01	-0.006371