Methodology and Quality Update

Latest Update on Methodology and Quality

3-8-2025

Statistical Presentation

Data description

The Railway Transport Statistics publication presents up-to-date statistics and indicators on railway transport in the Kingdom of Saudi Arabia.
It is a statistical product compiled from administrative record data and covers the main characteristics as follows:
•    Number of railway passengers.
•    Quantity of freight on railways.
•    Railway trips.
•    Lengths of the railway network.
•    Density of railway lines. 
•    Number of railway stations.
•    Railway infrastructure

Classifications

The following classifications are applied in the Railway Transport Statistics.
The National Classification for Economic Activities (ISIC4):
It is a statistical classification based on the International Standard Industrial Classification of All Economic Activities (ISIC4), used to describe the productive activities of an establishment . 
National Code of Countries and Nationalities (3166 ISO – codes Country):
A statistical classification based on the international standard  (ISO 3166_Country codes), which is a standard issued by the International Organization for Standardization (ISO of the UN), and this classification gives numeric and literal codes for the world’s (248) countries, based on the classification of countries. 
The classification is used in the Railway Transport publication to classify Saudi or non-Saudi individuals.
Metadata is collected from administrative record data sources to ensure that outputs are produced by all relevant classifications.
Classifications are available on the GASTAT website:  www.stats.gov.sa

Statistical concepts and definitions

Terminologies and concepts of the Railway Transport Statistics publication:
•    Train: 
The train is a series of connected carriages that run along a railway track.
•    Passenger:
Anyone presents in a means of transport, boarding or disembarking from it, other than the
driver.
•    Train station: 
A railway facility used for loading and unloading passengers or goods to form trains, dispatching, and receiving them, temporarily storing them, or for the assembly and maintenance of railway carriages.
•    Passenger station:
A train station for passenger traffic equipped with special facilities for passenger access and related services.
•    Railway carriage: 
A unit used to carry passengers or cargo. It is either a trailer pulled by a locomotive, or a self-propelled vehicle.
•    Passenger-kilometers: 
A unit of measurement that represents the transportation of one passenger by rail over a distance of one kilometer.
•    Ton-kilometers: 
A unit of measurement for freight transport, representing the transportation of one ton of goods over a distance of one kilometer.
•    Average fare per passenger: 
Revenue generated from passenger transport / Number of passengers
•    Average fare per passenger-kilometer: 
Average fare per passenger / Average trip length for passenger transport.
•    Average travel length for passenger transport: 
Total passenger kilometers traveled / Number of passengers.
•    Locomotives: 
Locomotive: Is the engine (train head).
•    Average number of seats per carriage:
Number of seats and beds / Total number of carriages.
•    Average travel length for freight transport: 
Number of ton-kilometers traveled / Amount of goods transported.
•    Kilometer:
    An international unit of measurement for length in the metric system, equal to 1,000
meters or 0.62 miles, and it is the unit used to measure distances between geographical
locations on the earth in most countries.

•    Revenue: 
The income that a company, factory, or commercial organization earns from its business activity, which is usually the revenue from the sale of goods or services to buyers.
•    Tons:
A megagram is a unit of measurement equivalent to 1,000 kilograms, and a ton is primarily used as a unit of mass, as well as a unit of volume.

•    Rail freight load factor:
It is the ratio of the actual freight transported (in ton-kilometers) to the total available transport capacity (in gross ton-kilometers or wagon-kilometers) over a specific period or distance.
•    Rail passenger load factor:
It is the ratio of the actual passenger kilometers traveled (passenger-kilometers) to the total available seat capacity (seat-kilometers) over a specific period.

Data sources

Railway transport statistics rely on a variety of data sources, including administrative record data available at the Transport General Authority, statistical models used in spatial analysis, and supporting secondary sources such as population census data and other related official data. The purpose of this diversity in sources is to enhance the accuracy of analysis and the comprehensiveness of spatial coverage.
The main published variables from the administrative record data source are:
•    Passenger traffic on railways.
•    Freight traffic on railways.
•    Transport equipment.
The main variables published from the statistical models used in spatial analysis:
•    Railway network density by area at the governorate and administrative region levels.
•    Railway network density by population at the administrative region level.
•    Lengths of the railway network.

Designing the data collection tool

Not applicable.

Questionnaire test (cognitive test)

Not applicable.

Statistical population

The targeted statistical population consists of all entities engaged in the operation or management of rail transport services, whether for passengers or freight, including train operators, infrastructure owners and operators, transport stations, and supporting facilities.

Sample Design

Not applicable.

Statistical unit (sampling unit)

The entity operating the railway transport service (whether for passenger or freight transport) serves as the primary source of data related to movement, volumes, and performance.

Data collection

Administrative record data is collected in coordination with the departments of the Authority responsible for data collection and management. The administrative record data for the Railway Transport Statistics Publication is obtained from the Transport General Authority, and it includes data on the number of trips, passengers, freight volumes, as well as statistical data related to the railway transport sector .
The data is stored in the Authority’s databases after undergoing auditing and review using established statistical methods and recognized quality standards regarding the data source in case any errors or remarks related to the data are detected.

Data collection frequency 

Annual.

Reference area

The Railway Transport Statistics publication covers all railway lines in the Kingdom of Saudi Arabia.

Reference period (time reference)

Data from administrative records data is based on the last day of the reference year.

Base period

Not applicable.

Measurement unit

•    Most results are measured in figures (number of flights, number of passengers) (in thousands or millions).
•    Some indicators are reported as rates (such as: Cargo Quantities).
•    And some results are calculated in kilometers (e.g.: Lengths of the railway)
•    Some results are calculated as percentages (e.g., Rate of change for flight, passengers, or quantities of freight.

Time coverage

Data is available for some indicators as a time series from 2017 to 2024.

Publication frequency

Annual.

Statistical processing

Error detection

Data are reviewed and matched to ensure their accuracy and precision in a way that suits their nature with the aim of giving the presented statistics quality and accuracy. 
The data of the current year publication are compared with the data of the previous year to ensure their integrity and consistency in preparation for processing data and extracting and reviewing results.
In addition to the data processing and tabulation to check their accuracy, all the outputs are stored and uploaded to the database after being calculated by GASTAT to be reviewed and processed by specialists in Health and Education Statistics through modern technologies and software designed for this purpose.

Data integration and matching from multiple sources 

Some railway indicators have been calculated using spatial and statistical modeling:
Data sources:
•    Railway lengths – Transport General Authority.
•    Population estimates – General Authority for Statistics
•    Administrative boundaries of regions and governorates – General Authority for Statistics.
Spatial and statistical modeling:
•    Integration of railway data.
•    Calculation of railway density by governorate for each administrative region.
•    Measurement of railway network lengths.
•    Determining railway density relative to the population for each administrative region.
Calculated indicators or variables:
•    Railway network density by area at the governorate and administrative region levels.
•    Railway network density by population at the administrative region level.
•    Lengths of railway network.
Applied statistical estimation:
The General Authority for Statistics relied on the approved formulas to calculate the key indicators of the Railway Transport Statistics as follows.
•    Railway network length per capita by administrative region = Total railway network length in the administrative region / Population of the administrative region.
•    Railway network length per square kilometer in the administrative region = Total railway network length in the administrative region / Area of the administrative region.

Imputation and calibration

Not applicable

Seasonal adjustments

Not applicable

Adjustment of preliminary results 

Not applicable, only final results will be published.

Quality dimensions

Suitability

A criterion that indicates how well the product meets users’ needs.

User needs 

Internal users at GASTAT of the Railway Transport Statistics publication data:
•    Tourism, Hajj, and Umrah Statistics.
•    International indicators.
Several external users and beneficiaries greatly benefit from the Railway Transport Statistics publication data, including:
•    Government entities.
•    Regional and international organizations.
•    Research institutions.
•    Media.
•    Individuals.

 The disseminated key variables used by external users:

Completeness 

The data in the Railway Transport Statistics publication is based primarily on administrative records data available at the Transport General Authority, statistical models used in spatial analysis, as well as supporting secondary sources such as population census data and other related official data. This approach aims to provide comprehensive information on railway transport with complete data coverage.

Accuracy and reliability 

A standard that measures how close the calculations or estimates are to the exact or true values that reflect reality.

Overall accuracy 

•    Data is checked with previous years to identify any significant changes in the data.
•    The internal consistency of the data is checked before it is finalized.
•    The links between variables are checked and coherence between different data series is confirmed.

Timeliness and punctuality 

A standard that measures the time gap between the availability of information and the occurrence of the event.
However, timeliness reflects the time difference between the date of data publication and the target date when it is actually published.

Timeliness 

The General Authority for Statistics is committed to applying internationally recognized standards regarding the announcement, clarification of the time of publishing statistics on its official website, as outlined in the statistical calendar, as well as adhering to the announced time of publication. In the event of any delay, updates will be provided accordingly.

Punctuality 

The publication takes place according to the published release dates on the statistical calendar for Railway Transport Statistics Publication on the website of the General Authority for Statistics.
The data are available at the expected time, as scheduled in the statistical release calendar, If the publication is delayed, reasons shall be provided.

Coherence and comparability

A standard that refers to the necessity of internal and temporal consistency of statistics, their logical coherence, and their comparability and integration across different regions and sources.

Comparability - geographical

The data follow unified international definitions and standards, ensuring their geographical comparability.

Comparability - over time 

The data are comparable over time, as no changes have been made to the methodology used.

Coherence- Cross domain

The same definitions and classifications are used when comparing railway transport with other means of transport, as a unified definition for the passenger transport indicator across different means is applied within Land Transport, Railway Transport, Air Transport, and Maritime Transport statistics publications to facilitate comparison.

Coherence- Sub-annual and annual statistics 

Transport General Authority calculates annual indicators for all entities engaged in railway transport activities in the Kingdom, ensuring that the annual aggregates are consistent with administrative records and historical data.

Coherence- National Accounts 

Not applicable

Coherence- Internal 

Railway transport data is characterized by internal consistency, as logical checks are applied to verify the coherence of values among variables such as the number of passengers, distances, and passenger-kilometers.

Accessibility and clarity

The ability for users to access data, the availability of accurate or complete data, and the availability of a methodology and quality report.

Press releases

The announcements for each publication are available on the statistical calendar as mentioned in 10.1. The press releases can be viewed on the website of GASTAT on the link: 
Press release

Publications

The General Authority for Statistics regularly issues publications and reports on railway transport statistics according to a pre-prepared release schedule, and they are published on the Authority’s website. The Authority is keen to publish its results in a way that serves all types of users, including publications in various formats containing publication tables, data graphs, indicators, and methodology and quality reports in both English and Arabic
 .
The results of the Railway Transport Statistics are available at:
Statistics 

On-line database

Not available.

Microdata accessibility

Not available.

References and standards

The General Authority for Statistics adopts a unified methodology in carrying out all its statistical work, by the nature of each statistical product. It relies on the Generic Statistical Business Process Model (GSBPM), which aligns with the procedures adopted by international organizations, and is implemented in coordination with relevant authorities to ensure the quality and efficiency of statistical operations. For more details, you can refer to the Generic Statistical Business Process Model (GSBPM) via the following link:
Generic Statistical Business Process Model (GSBPM)
Regarding the definitions and concepts used, Railway Transport Statistics are based on the Transport Statistics Glossary, a document prepared by the joint working group between the secretariats of Eurostat, the International Transport Forum, and the United Nations Economic Commission for Europe – fourth edition
https://ec.europa.eu/eurostat/documents/3859598/10013293/KS-GQ-19-004-EN-N.pdf/b89e58d3-72ca-49e0-a353-b4ea0dc8988f?t=1568383761000 
It is also based on the ESCWA Glossary of Statistical Terms.

Quality assurance

GASTAT considers the following principles: Impartiality, ensuring that the statistical product is user-oriented, maintaining the quality of processes and outputs, enhancing the effectiveness of statistical operations, and reducing the burden on respondents. 
Data is validated through procedures and quality controls that are applied during the process at various stages, such as: (data entry, data collection, and other final controls).

Quality assessment

GASTAT performs all statistical activities according to a national model (Generic Statistical Business Process Model – GSBPM). According to the GSBPM, the final stage of statistical activities is overall evaluation using information gathered in each stage or sub-process. This information is used to prepare the evaluation report, which outlines all the quality issues related to the specific statistical activity and serves as input for improvement actions.

Confidentiality

Confidentiality - Policy

According to Royal Decree No. 23 dated 07/12/1397, data must always be kept confidential and must be used by GASTAT for statistical purposes only.
Therefore, the data is protected in the data servers of GASTAT.

Confidentiality - Data Treatment

Data were displayed in appropriate tables to facilitate their summarization, comprehension, and results extraction. Also, to compare data with other data and extract statistical meanings for the study community. It is also easier to check tables without the need to see any sensitive or confidential data, which violates the confidentiality of statistical data.

Publishing policy

Statistical calendar

Railway Transport Statistics have been included in the statistical calendar.
Statistical Calendar

User access

One of GASTAT’s objectives is to better meet its clients' needs, so it immediately provides them with the results once the Railway Transport Statistics publication is published.
It also receives questions and inquiries from clients about the publication and its results through various communication channels, such as:
•    GASTAT official website:  www.stats.gov.sa
•    GASTAT official e-mail address:  info@stats.gov.sa
•    Client support e-mail address: info@stats.gov.sa
•    Official visits to GASTAT’s official head office in Riyadh or one of its branches in Saudi Arabia.
•    Official letters.
•    Statistical telephone: (199009).