Quarter	Millions of US Dollars
1972-10-01	20
1973-01-01	20
1973-04-01	45
1973-07-01	45
1973-10-01	42
1974-01-01	44
1974-04-01	43
1974-07-01	43
1974-10-01	45
1975-01-01	46
1975-04-01	45
1975-07-01	43
1975-10-01	73
1976-01-01	74
1976-04-01	73
1976-07-01	75
1976-10-01	75
1977-01-01	105
1977-04-01	157
1977-07-01	158
1977-10-01	165
1978-01-01	214
1978-04-01	216
1978-07-01	252
1978-10-01	258
1979-01-01	251
1979-04-01	250
1979-07-01	257
1979-10-01	255
1980-01-01	238
1980-04-01	257
1980-07-01	254
1980-10-01	227
1981-01-01	217
1981-04-01	200
1981-07-01	202
1981-10-01	178
1982-01-01	166
1982-04-01	163
1982-07-01	158
1982-10-01	169
1983-01-01	167
1983-04-01	162
1983-07-01	160
1983-10-01	157
1984-01-01	133
1984-04-01	125
1984-07-01	100
1984-10-01	97
1985-01-01	98
1985-04-01	79
1985-07-01	91
1985-10-01	74
1986-01-01	82
1986-04-01	88
1986-07-01	94
1986-10-01	94
1987-01-01	102
1987-04-01	101
1987-07-01	68
1987-10-01	82
2002-07-01	616
2002-10-01	1049
2003-01-01	1090
2003-04-01	1143
2003-07-01	1165
2003-10-01	1263
2004-01-01	1222
2004-04-01	1215
2004-07-01	1241
2004-10-01	1362
2005-01-01	1296
2005-04-01	1209
2005-07-01	1204
2005-10-01	1180
2006-01-01	1210
2006-04-01	1271
2006-07-01	1266
2006-10-01	1317
2007-01-01	1332
2007-04-01	1351
2007-07-01	532
2007-10-01	552
2008-01-01	593