Quarter US dollars 2004-12-31 4254 2005-03-31 5970 2005-06-30 3415 2005-09-30 6918 2005-12-31 2501 2006-03-31 4609 2006-06-30 5500 2006-09-30 8442 2006-12-31 3861 2007-03-31 5129 2007-06-30 10750 2007-09-30 7280 2007-12-31 9080 2008-03-31 11126 2008-06-30 9061 2008-09-30 8330 2008-12-31 6650 2009-03-31 8073 2009-06-30 6497 2009-09-30 8724 2009-12-31 11090 2010-03-31 13220 2010-06-30 17989 2010-09-30 16938 2010-12-31 20452 2011-03-31 23721 2011-06-30 24359 2011-09-30 23228 2011-12-31 21563 2012-03-31 16305 2012-06-30 16141 2012-09-30 18169 2012-12-31 21469 2013-03-31 23506 2013-06-30 26758 2013-09-30 23978 2013-12-31 25417 2014-03-31 25516 2014-06-30 21228 2014-09-30 22322 2014-12-31 23026 2015-03-31 22817 2015-06-30 19473 2015-09-30 18687 2015-12-31 17463 2016-03-31 17346 2016-06-30 17490 2016-09-30 17426 2016-12-31 17457 2017-03-31 21487 2017-06-30 20781 2017-09-30 21405 2017-12-31 22029 2018-03-31 24889 2018-06-30 21970 2018-09-30 21160 2018-12-31 21403 2019-03-31 21355 2019-06-30 18531 2019-09-30 17221 2019-12-31 17719 2020-03-31 16444 2020-06-30 15735 2020-09-30 15529 2020-12-31 17741 2021-03-31 20126 2021-06-30 17556 2021-09-30 19747 2021-12-31 19831 2022-03-31 20231 2022-06-30 16686 2022-09-30 15391 2022-12-31 15156 2023-03-31 15558 2023-06-30 12284 2023-09-30 11713