Year total route-km 1980 32013 1981 32015 1982 32015 1983 31987 1984 32149.5 1985 32149.5 1986 32203.5 1987 32062.5 1988 32059.5 1989 32047.5 1990 31624.5 1991 31491 1992 31494 1993 31482 1994 31590 1995 31547 1996 31468 1997 31555 1998 31555 1999 31671.5 2000 30983 2001 30991 2002 31095 2003 31119 2004 31788 2005 30635 2006 30643 2007 30635 2008 30224 2009 29788 2010 29788 2011 29988 2012 29593 2013 29592.5 2014 29592 2015 29592 2016 29592