Year	total route-km
1980	36470
1981	36482
1982	36544
1983	36604
1984	36792
1985	37250
1986	37244
1987	37071.65
1988	37124.65
1989	37167
1990	36894.585483871
1991	37288.585483871
1992	37915.585483871
1993	36990.945483871
1994	36992.945483871
1995	37047.035483871
1996	36968.035483871
1997	37082.445483871
1998	37082.445483871
1999	37233.435483871
2000	36500.935483871
2001	36498.935483871
2002	36475.935483871
2003	36589.935483871
2004	37489.935483871
2005	37356.935483871
2006	36697.935483871
2007	36697.935483871
2008	36359.935483871
2009	35923.935483871
2010	35928.935483871
2011	36128.935483871
2012	35733.935483871
2013	35733.935483871
2014	35733.935483871
2015	35716.935483871
2016	35716.935483871