Year	total route-km
1980	21183
1981	21183
1982	21198
1983	21170
1984	21152.5
1985	21155.8
1986	20611.8
1987	20762.8
1988	20763.37
1989	20744.37
1990	20744.37
1991	25405.87
1992	24904.87
1993	24894.87
1994	25675.87
1995	26081.87
1996	21541
1997	24936
1998	21431
1999	21431
2000	25177
2001	21630
2002	25742
2003	25742
2004	25511
2005	24663
2006	24750
2007	24733
2008	24787
2009	24792
2010	24789
2011	24824
2012	24758
2013	24757.5
2014	24757
2015	26253
2016	26319