Year	total route-km
1980	557178.435483871
1981	552923.387096774
1982	551088.1
1983	546742.941935484
1984	537283.064516129
1985	525336.925806452
1986	513949.938709677
1987	499385.664516129
1988	491046.470967742
1989	488833.54516129
1990	520858.364516129
1991	515635.851612903
1992	505553.887096774
1993	516095.838709677
1994	512571.335483871
1995	511185.35483871
1996	517047.517296862
1997	511324.32689211
1998	508180.47020934
1999	507454.721417069
2000	506910
2001	497675.297906602
2002	500789.703703704
2003	499509.00805153
2004	496853.00805153
2005	498855.00805153
2006	570559
2007	565891
2008	567515
2009	570975
2010	590001
2011	569190
2012	563994
2013	564226
2014	563063
2015	559740.83
2016	559013.52