Quarter US dollars 2004-12-31 13 2005-03-31 13 2005-06-30 7 2005-09-30 7 2005-12-31 9 2006-03-31 9 2006-06-30 7 2006-09-30 7 2006-12-31 8 2007-03-31 8 2007-06-30 22 2007-09-30 24 2007-12-31 30 2008-03-31 30 2008-06-30 30 2008-09-30 32 2008-12-31 29 2009-03-31 26 2009-06-30 25 2009-09-30 30 2009-12-31 32 2010-03-31 27 2010-06-30 24 2010-09-30 28 2010-12-31 25 2011-03-31 27 2011-06-30 27 2011-09-30 22 2011-12-31 20 2012-03-31 22 2012-06-30 20 2012-09-30 21 2012-12-31 23 2013-03-31 21 2013-06-30 89 2013-09-30 74 2013-12-31 26 2014-03-31 23 2014-06-30 24 2014-09-30 0 2014-12-31 2 2015-03-31 3 2015-06-30 5 2015-09-30 2 2015-12-31 3 2016-03-31 0 2016-06-30 1 2016-09-30 1 2016-12-31 1 2017-03-31 1 2017-06-30 1 2017-09-30 1 2017-12-31 5 2018-03-31 27 2018-06-30 26 2018-09-30 25 2018-12-31 26 2019-03-31 18 2019-06-30 1 2019-09-30 0 2019-12-31 0 2020-03-31 1 2020-06-30 1 2020-09-30 0 2020-12-31 1 2021-03-31 1 2021-06-30 10 2021-09-30 1 2021-12-31 1 2022-03-31 1 2022-06-30 0 2022-09-30 2 2022-12-31 1 2023-03-31 1 2023-06-30 1 2023-09-30 0