Year	total route-km
1980	34927
1981	34929
1982	34929
1983	34901
1984	35046.5
1985	35046.8
1986	35100.8
1987	34959.8
1988	34956.5
1989	34925.5
1990	34499.5
1991	34411
1992	33911
1993	33899
1994	34682
1995	35142
1996	31506
1997	35098
1998	31593
1999	31709.5
2000	34472
2001	30923
2002	34532
2003	34532
2004	35201
2005	33354
2006	33362
2007	33354
2008	33101
2009	32658
2010	32658
2011	32971
2012	32576
2013	32575.5
2014	32575
2015	32575
2016	32575