Quarter	US dollars
1999-03-31	25940
1999-06-30	22646
1999-09-30	25079
1999-12-31	22563
2000-03-31	28423
2000-06-30	27968
2000-09-30	27785
2000-12-31	33984
2001-03-31	31716
2001-06-30	29882
2001-09-30	32781
2001-12-31	33239
2002-03-31	32290
2002-06-30	34207
2002-09-30	33521
2002-12-31	36874
2003-03-31	42847
2003-06-30	41176
2003-09-30	38633
2003-12-31	35874
2004-03-31	33939
2004-06-30	37424
2004-09-30	37773
2004-12-31	36674
2005-03-31	37894
2005-06-30	38334
2005-09-30	34870
2005-12-31	34659
2006-03-31	45418
2006-06-30	44385
2006-09-30	38943
2006-12-31	41562
2007-03-31	47832
2007-06-30	49280
2007-09-30	48301
2007-12-31	52292
2008-03-31	58774
2008-06-30	53803
2008-09-30	50173
2008-12-31	42297
2009-03-31	40343
2009-06-30	40625
2009-09-30	35858
2009-12-31	36494
2010-03-31	32713
2010-06-30	32234
2010-09-30	34783
2010-12-31	35822
2011-03-31	40067
2011-06-30	40082
2011-09-30	46973
2011-12-31	79732
2012-03-31	45720
2012-06-30	50236
2012-09-30	50072
2012-12-31	45554
2013-03-31	42869
2013-06-30	43759
2013-09-30	45467
2013-12-31	46387
2014-03-31	45820
2014-06-30	42218
2014-09-30	39325
2014-12-31	36188
2015-03-31	39216
2015-06-30	26344
2015-09-30	22242
2015-12-31	22113