Year % net 1983 1.67287 1986 2.39686 1989 3.63422 1992 4.65139 1993 4.78067 1994 4.91482 1999 6.44441 2001 6.32618 2003 7.67682 2004 8.56467 2005 9.41725 2006 10.1525 2007 10.81736 2008 12.50616 2009 13.44634 2010 14.38973 2011 16.38828 2012 17.88729 2013 20.16338 2015 25.91824 2016 28.00193 2017 29.33465 2018 31.69258