Explanatory Notes on Main Statistical Indicators

Length of Railways in Operation refers to the total length of the trunk line under passenger and freight transportation．The calculation is based on the actual length of the first line even if this line has a full or partial double track or more tracks，excluding double tracks，station sidings, tracks under the charge of stations, branch lines, special-purpose lines and the non-payable connecting lines. The length of railways in operation is an important indicator to show the development of the infrastructure for the railway transport，and also the essential data to calculate volume of passenger freight transport，traffic density and utilization efficiency of the locomotives and carriages．

Extenuation Length of Trunk Lines refers to the sum of the first，the second，the third lines and other constructed length of the trunk railways，excluding the extenuation length of the station lines, lines under the jurisdiction of depots, sidings and lines for special purpose．It provides important information for the calculation of the needs for rails，sleepers，sand and stone for the construction of railways．

Length of Electrified Railways refers to the length of the section of railways in operation in which the power supply lines and other equipment are installed for the running of electrified locomotives．The proportion of the length of electrified railways to the total length of railways in operation is an important indicator to show the modernization of railways．

Automatic-blocking Length of Railways: Blocking is a spacing technique by which a section of the railway only allows one train to pass at a time，in order to ensure the traffic safety. Automatic blocking length of railways refers to railways installed with equipment to perform automatic blocking of trains，the proportion of automaticblocking length to the total length of railways in operation is an important indicator to show the modernization of railways．

Length of Highways refers to the length of highways which are built in conformity with the grades specified by the highway engineering standard formulated by the Ministry of Communications, and have been formally checked and accepted by the departments of highways and put into use. The length of highways includes that of the suburb highways at large and medium-sized cities，highways passing through streets at small cities and towns，and also the length of bridges and ferries．It does not include the length of streets in big and medium-sized cities and highways built for the production purpose at factories，mines，forest areas and agricultural areas．If two or more highways go the same section of the way，the length of the section is only calculated for once and no duplication is allowed. The length of highways is an important indicator to show the development of the highway construction and to provide essential information to calculate the transport network density．

Length of Navigable Inland Waterways an indicator reflecting the size and development of inland water network, it refers to the length of the natural rivers，lakes，reservoirs，canals，and ditches open to navigation during a given period, which enables the transport by ships and rafts．It includes the channels open to navigation for over an accumulative 3 months in a year，yet this does not include the river courses which are only used to float odd logs and bamboo rafts．

Length of Civil Aviation Routes refers to the length of all routes for regular civil aviation flights．There are usually two ways to calculate the distance between airports connected by the route length：One is to put the length of all air routes together，called duplicated calculation of the length of the routes；the other is not to allow the duplication in calculation when two or more routes passing the same section of aviation routes. The latter is usually used，as it can precisely show the size of the civil aviation network and indicate the extent of civil aviation serving the national economy and the people．

Length of Oil（Gas）Pipelines used as an indicator to show the development，scale and level of the pipeline transportation, it refers to the actual transport distance of oil（or gas）products，and is in general calculated in the length of single pipe line. If the length of the double pipelines and alternate pipeline are included, it is called the extension length of the oil (gas) pipelines, which indicates the actual length of the pipelines built, excluding double pipelines.

Freight（Passenger）Traffic refers to the volume of freight（passenger）transported with various means. Freight transport is calculated in tons and passenger traffic is calculated in the number of persons. Despite the type of freight and travelling distance，the freight transport is calculated in the actual weight of the goods：and despite the travelling distance and ticket price，the passenger traffic is calculated by the principle that one person can be counted only once in one travel. The passenger who travel with a halfprice ticket or a child ticket is also calculated as one person．The freight（passenger）traffic provides a quantitative measure to show how the transport industry serves the national economy and people，and is also an important indicator for planning the transport industry and for studying the development scale and speed of the transport industry．

Freight（Passenger）Traffic Density refers to the freight （passenger）traffic volume carried by a particular means of transportation during a given period through one kilometer of a specific section of transportation route. The formula is as follows：

Freight（Passenger） Traffic Density ＝ Freight Ton-kilometers （Passenger-kilometers) / Length of Route in Operation

Freight（passenger）traffic density reflects the degree of business of freight（passenger）traffic on transportation routes，and therefore provides important information for balancing transport capability，planning construction and upgrading of transport routes and studying the distribution of transport network．

Freight Ton-kilometers （Passenger-kilometers） refer to the sum of the products of the volume of transported cargo（passengers） multiplying by the transport distance，usually using ton-kilometer and passenger-kilometer as units for measurement．Normally，the shortest distance between the departure station and the destination station (i.e., the payable distance) is the basis to calculate the freight ton-kilometers. This is an important indicator to show the total results of the transport industry，to prepare and examine the transport plan and to measure the efficiency，the labour productivity and the unit cost of transport．

Static Load of Freight Cars refers to the average cargo weight as loaded by each freight car under the static condition at the departure station. It is used to show the utilization extent of the loading capacity of the freight cars. The formula is：

Static Load（ton）of Freight Car＝Tonnage of Goods Dispatched

Number of Freight Cars LoadedThe static load of freight cars is determined by the nature and type of goods loaded，the type of vehicles，and the technique of loading．The difference between the average marked load and the static load of freight cars reflects the utilization of loading capacity of freight cars．For its calculation the following formula is applied:

Utilization Rate of Capacity of Freight Cars（％）＝Average Static Load Average Marked Load 100％ 

Average Daily Haul of Freight Locomotives refers to the average total tonkilometers accomplished by each freight transport locomotive over day and night．It includes both the weight of the goods carried and the dead weight of the train itself．It is a comprehensive indicator reflecting the locomotive efficiency in terms of both time and the pulling force．

Average Daily Haul of Freight Transport Locomotive ＝ Total Ton／Kilometers of Freight Daily Number of Freight Transport Locomotive

Volume of Freight Handled in Major Coastal Ports refers to the volume of cargo passing in and out the harbor area of the major coastal ports and having been loaded and unloaded. The volume includes that of the postal matters, registered luggage and fuels, materials and fresh water as supplies of the ships. The volume of freight handled may be classified as import，export，or as domestic trade and foreign trade．The volume of freight handled by type of cargo and by main flow direction reflects the position and function of the ports in the inflow of Chinese and foreign commodities and in the transportation for foreign trade．

Business Volume of Post and Telecommunications refers to the total amount of post and telecommunications services, expressed in value terms, provided by the post and telecommunications departments for the customers．Post and telecommunication services can be classified as letters, parcels, remittance, issue of newspapers and magazines, fast mail service, express mail service, savings deposits, stamps for collection, public and individual telegraph service, facsimiles, long-distance telephone service, leasing of telephone lines, urban paging service, mobile telephone service, data transfer and transmission, etc. The accounting approach is to multiply the service products of all types with their average unit price (constant price) to get sum of business value, plus income from other services such as leasing of telephone lines and equipment, maintenance of telephone switchboards and lines on behalf of customers. This indicator reflects the overall results of post and telecommunications service during a given period, and is important to study the composition of business service and the development of post and telecommunications service.

Subscribers of Paging Services refer to subscribers who carry small-size pagers and receive audio signals，digital signals or character signals sent out by city telephone through wireless paging center within assigned area．Each pager is counted as a subscriber．

Mobile Telephone Subscribers refer to the persons who own mobile telephone number connected with the mobile telephone communication network and registered by post and telecommunications organization． The number of subscribers is calculated only when the subscribers who have gone through all the register formalities and entered into the mobile telephone network．One mobile telephone is treated as a subscriber.

Since 1997, the classification of telephone subscribers and number of telephones was modified on the basis of physical location of the subscribers as "urban telephone subscribers" and "rural telephone subscribers", which is different from the previous classification of categorizing "local telephones" and "rural telephones", while the definition of total subscribers and total number of telephones remain unchanged.

1. Urban telephone subscribers: refer to telephone subscribers connected to exchanges installed in the urban and suburban districts of cities under the jurisdiction of central and provincial governments, of cities at prefecture or county levels, and in county towns (including towns where the county government is located). They also include subscribers connected to exchanges installed in independent industrial and mining zones, forest zones and military institutions located in rural areas.

2. Rural telephone subscribers: refer to telephone subscribers connected to exchanges installed in small towns and in rural areas.3. Household telephone subscribers: refer to telephone sets installed in the dwelling units of residents, include 3 types of payment for the service: private payment, public payment and free service.

4. Private-paid telephone subscribers: refer to subscribers who pay for the installation and service of telephones.