Year Sterling 1997-12-31 11905 1998-12-31 12603 1999-12-31 13664 2000-12-31 12263 2001-12-31 11989 2002-12-31 12424 2003-12-31 11144 2004-12-31 12329 2005-12-31 12315 2006-12-31 13960 2007-12-31 12932 2008-12-31 12741 2009-12-31 14217 2010-12-31 13637 2011-12-31 12965 2012-12-31 12125 2013-12-31 11726 2014-12-31 13062 2015-12-31 15563 2016-12-31 16973 2017-12-31 17727 2018-12-31 17583 2019-12-31 14048 2020-12-31 14103 2021-12-31 12165 2022-12-31 12812 2023-12-31 11623