Year Number 2004-01-01 0.2230 2005-01-01 1.5918 2006-01-01 1.0916 2007-01-01 1.5404 2008-01-01 0.9771 2009-01-01 0.2666 2010-01-01 0.0383 2011-01-01 0.0002 2012-01-01 0.0017