Year	total route-km
1980	181238.5
1981	181014
1982	181923.1
1983	182093.2
1984	181449
1985	179964.7
1986	179379.1
1987	178749.6
1988	178202.6
1989	177483.9
1990	217212.3
1991	217681.4
1992	213103.5
1993	227818
1994	225813.4
1995	225377
1996	222896.66
1997	221158
1998	220532
1999	221575
2000	221256
2001	214569
2002	214814
2003	214877
2004	211958
2005	213241
2006	217020
2007	212616
2008	214011
2009	217668
2010	233397
2011	218379
2012	213307
2013	213398
2014	211462
2015	210722.76
2016	211408.69