Quarter US dollars 2004-12-31 17588 2005-03-31 17658 2005-06-30 20399 2005-09-30 19471 2005-12-31 21883 2006-03-31 22143 2006-06-30 23214 2006-09-30 22990 2006-12-31 24930 2007-03-31 23891 2007-06-30 25481 2007-09-30 27216 2007-12-31 29266 2008-03-31 29759 2008-06-30 30381 2008-09-30 29515 2008-12-31 24548 2009-03-31 23620 2009-06-30 24957 2009-09-30 22763 2009-12-31 23377 2010-03-31 28226 2010-06-30 27564 2010-09-30 30147 2010-12-31 29680 2011-03-31 32921 2011-06-30 36221 2011-09-30 30951 2011-12-31 31877 2012-03-31 34910 2012-06-30 33460 2012-09-30 32505 2012-12-31 33363 2013-03-31 32554 2013-06-30 30103 2013-09-30 28798 2013-12-31 31554 2014-03-31 31592 2014-06-30 35160 2014-09-30 34596 2014-12-31 32174 2015-03-31 29920 2015-06-30 27435 2015-09-30 24187 2015-12-31 24638 2016-03-31 28698 2016-06-30 24629 2016-09-30 23060 2016-12-31 22470 2017-03-31 24547 2017-06-30 26558 2017-09-30 27133 2017-12-31 27900 2018-03-31 30356 2018-06-30 28975 2018-09-30 31014 2018-12-31 31594 2019-03-31 33595 2019-06-30 33756 2019-09-30 32503 2019-12-31 33401 2020-03-31 27463 2020-06-30 29287 2020-09-30 27425 2020-12-31 30482 2021-03-31 28795 2021-06-30 30663 2021-09-30 29705 2021-12-31 29233 2022-03-31 31287 2022-06-30 30915 2022-09-30 32007 2022-12-31 33893 2023-03-31 36142 2023-06-30 39100 2023-09-30 39597