Quarter	Thousands
1997-12-31	59465
1998-03-31	64788
1998-06-30	75160
1998-09-30	83958
1998-12-31	89096
1999-03-31	109782
1999-06-30	121970
1999-09-30	128880
1999-12-31	112448
2000-03-31	104679
2000-06-30	122438
2000-09-30	140700
2000-12-31	129967
2001-03-31	143231
2001-06-30	161268
2001-09-30	164673
2001-12-31	163746
2002-03-31	171355
2002-06-30	203150
2002-09-30	216732
2002-12-31	222394
2003-03-31	241515
2003-06-30	260990
2003-09-30	279805
2003-12-31	241052
2004-03-31	233028
2004-06-30	226742
2004-09-30	213866
2004-12-31	147042
2005-03-31	146959
2005-06-30	170947
2005-09-30	165413
2005-12-31	141253
2006-03-31	153960
2006-06-30	159817
2006-09-30	159973
2006-12-31	144812
2007-03-31	155833
2007-06-30	151523
2007-09-30	143132
2007-12-31	113098
2008-03-31	121762
2008-06-30	101818
2008-09-30	91558
2008-12-31	66757
2009-03-31	74925
2009-06-30	65535
2009-09-30	65316
2009-12-31	59183