Quarter	Millions of US Dollars
1972-01-01	35
1972-07-01	18
1973-01-01	28
1973-04-01	35
1973-07-01	10
1974-01-01	15
1974-10-01	34
1975-01-01	72
1975-04-01	87
1975-07-01	181
1975-10-01	332
1976-01-01	276
1976-04-01	216
1976-07-01	133
1976-10-01	147
1977-01-01	578
1977-04-01	380
1977-07-01	126
1977-10-01	416
1978-01-01	574
1978-04-01	508
1978-10-01	461
1979-01-01	385
1979-04-01	288
1979-07-01	136
1979-10-01	39
1980-01-01	207
1980-04-01	0
1980-07-01	-75
1980-10-01	-369
1981-01-01	-227
1981-04-01	-213
1981-07-01	-40
1981-10-01	-34
1982-01-01	-509
1982-04-01	-316
1982-07-01	-38
1982-10-01	-299
1983-01-01	-443
1983-04-01	-458
1983-10-01	-321
1984-01-01	-105
1984-04-01	-216
1984-07-01	-71
1984-10-01	-38
1985-01-01	-113
1985-04-01	-16
1985-07-01	-30
1985-10-01	-198
1986-01-01	4
1986-04-01	-23
1986-07-01	500
1986-10-01	453
1987-01-01	56
1987-04-01	745
1987-07-01	-173
1987-10-01	-252
1988-01-01	489
1988-04-01	352
1988-07-01	-73
1988-10-01	-7
1989-01-01	357
1989-07-01	-17
1989-10-01	-14
1990-01-01	-22
1990-04-01	-121
1990-07-01	-10
1990-10-01	-110
1991-01-01	-197
1991-04-01	-19
1991-07-01	642
1991-10-01	505
1992-01-01	1407
1992-04-01	1277
1992-07-01	-49
1992-10-01	154
1993-01-01	50
1993-04-01	1840
1993-07-01	-49
1993-10-01	-76
1994-01-01	-374
1994-04-01	-106
1994-10-01	-18
1995-01-01	-33
1995-04-01	-592
1995-07-01	-135
1995-10-01	-19
1996-01-01	-48
1996-07-01	-1274
1996-10-01	-1018
1997-01-01	-1994
1997-04-01	-1167
1998-01-01	-475
1998-04-01	-1335
1998-10-01	-324
1999-01-01	-38
2002-10-01	-200
2003-01-01	-497