Year Number 2004-01-01 9.8498 2005-01-01 9.5360 2006-01-01 9.2554 2007-01-01 9.2171 2008-01-01 8.9293 2009-01-01 8.9839 2010-01-01 8.9091 2011-01-01 8.6286 2012-01-01 7.9379