Year % net 1999 61.97265 2000 70.18143 2001 72.13134 2002 75.00605 2004 78.10509 2005 78.1815 2006 78.81148 2007 80.24331 2008 81.59779 2009 81.79476 2010 82.50797 2011 83.21746