15-5  Quality of Transport Routes
Item	1990	1995	2000	2006	2007
Length of National Railways in Operation (km)	53378	54616	58656	63412	63637
Double-Tracking Length                             (km)	13024	16909	21408	25244	25794
Proportion                                                     (%)	24.4	31.0	36.5	39.8	40.5
Automatic Blocking Length                        (km)	10370	12910	18318	25630	26526
Proportion                                                     (%)	19.4	23.6	31.2	40.4	41.7
Length of Highways                                     (km)	1028348	1157009	1402698	3456999	3583715
Expressway and Class I to IV Highways     (km)	741040	910754	1216013	2282872	2535383
Proportion                                                    (%)	72.1	78.7	86.7	66.0	70.7
Length of Navigable Inland Waterways    (km)	109192	110562	119325	123388	123495
Standard Waterways                                   (km)		56587	61367	61035	61197
Proportion                                                    (%)		51.2	51.4	49.5	49.6