Year % of internal resources 1985 2.32 1986 2.41824 1987 2.51648 1988 2.61472 1989 2.71296 1990 2.8112 1991 2.9096 1992 3.008 1993 3.1619555552 1994 3.3159111112000006 1995 3.4698666664 1996 3.6238222224 1997 3.7777777776 1998 4.64 1999 4.912 2000 5.184 2001 5.456 2002 5.728 2003 6 2004 6.272 2005 6.544 2006 6.544 2007 6.544 2008 6.544 2009 6.544 2010 6.544 2011 6.544 2012 6.544 2013 6.544 2014 6.544 2015 6.544 2016 6.544 2017 6.544 2018 6.544 2019 6.544 2020 6.544