Methodology and Quality Update

Methodology and Quality  last update

05/11/2024

Statistical Presentation

Data description  

Railway Transport Statistics publication presents up-to-date statistics and indicators on railway transport in the Kingdom of Saudi Arabia.
Railway Transport Statistics publication is a statistical product that collects data through administrative records about key characteristics as follows:
•    Number of railway passengers.
•    Quantity of freight on railways.
•    Railway flights.
•    Lengths of railway network.
•    Density of railway lines. 
•    Number of railway stations.
•    Railway infrastructure. 

Classification system

The following classifications are applied in Railway Transport Statistics:
The National Classification for Economic Activities (ISIC4):
The statistical classification based on the International Standard of Industrial Classification of All Economic Activities (ISIC4) is used to describe 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 are collected through registry data sources so that outputs can be produced in accordance with all relevant classifications.
The classifications are available on the GASTAT’s website: 

Sector coverage

The Railway Transport Statistics publication covers all railway transport activities in the Kingdom.

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 who is in the vehicle or is getting on or off 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-kilometres: 
A unit of measurement that represents the transportation of one passenger by rail over a distance of one kilometer.
•    Ton-kilometres: 
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-kilometre: 
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.
•    Kilometre:
 An international unit of length in the metric system, equal to 1000 meters or 0.62 miles. It is the unit used to measure distances between geographical locations on Earth in most countries around the world.
•    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.

Statistical unit

Not applicable.

Statistical population

Not applicable.

Reference area

All railway lines in the Kingdom of Saudi Arabia.

Time coverage

Data is available for some indicators as a time series from 2017 to 2023.
Base period
Not applicable. 

Unit of measure

•    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 kilometres (e.g.: Lengths of the railway)
•    some results are calculated as percentage (such as: Rate of change for flight, passengers, or quantities of freight.

Reference period

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

Confidentiality

Confidentiality – policy

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

Confidentiality - data treatment

Data are displayed in appropriate tables to facilitate its summarization, comprehension, results extraction. comparison with other data and coming up with statistical connotations 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.

Release policy
Release calendar

The Railway Transport Statistics Publication is included in the statistical calendar.

Release calendar access

Available on the: https://www.stats.gov.sa/statistical-calendar-releases

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User access

One of GASTAT’s objectives is to better meet its clients' needs, so it immediately provides them with the publication's results once the Railway Transport Statistics Publication is published.
 It also receives questions and inquiries of the 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: 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).

Frequency of dissemination

Annual. 

Accessibility and clarity

News release

The announcements of each publication are available on release calendar as mentioned in 7.2. Release calendar access. The news release can be viewed on the website of GASTAT through the following link:
https://www.stats.gov.sa/en/news

Publications

GASTAT issues the Railway Transport Statistics Publication on a regular basis within a pre-prepared dissemination plan and are published on GASTAT’s website. GASTAT is keen to publish its publications in a way that serves all users of different types, including publications in different formats that contain (publication tables, data graphs, indicators, methodology and quality report, methodology, and questionnaires) in both English and Arabic.
The results of the Railway Transport Statistics Publication are available at:
https://www.stats.gov.sa/en/statistics

On-line database

Not applicable.

Micro-data access 

Not applicable.

Other

Not available.

Documentation on methodology

The definitions and concepts are based on the Glossary for Transport Statistics , a document prepared by the Intersecretariat Working Group of Eurostat, the International Transport Union and the United Nations Commission for Europe, 4th edition, as well as the  ESCWA Glossary of Statistical Terms.

Quality documentation

Quality documentation covers documentation on methods and standards for assessing, measuring, and monitoring the quality of statistical process and output. It is based on standard quality criteria such as relevance, accuracy and reliability, timeliness and punctuality, accessibility and clarity, comparability, and coherence.

Quality management

Quality assurance

GASTAT declares that it considers the following principles: impartiality, user orientated, quality of processes and output, effectiveness of statistical processes, reducing the workload for respondents. 
Quality controls and validation of data are actions carried out throughout the process in different stages such as the data input and 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 phase of statistical activities is overall evaluation using information gathered in each phase 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.

Relevance 

User needs 

Internal users in the GASTAT for Railway Transport Statistics Publication data:
•    National accounts statistics.
•    Tourism, Hajj, and Umrah Statistics.
•    The statistical book.
•    Price statistics.
•    International indicators.
Some several external users and beneficiaries greatly benefit from Railway Transport Statistics Publication data, including:
•    Government entities.
•    Regional and international organizations.
•    Research institutions.
•    Media.
•    Individuals.

The disseminated key variables that mostly used by key users: 

User satisfaction

Not available.

Completeness 

The data in the Railway Transport Statistics Bulletin is based on the primary source of record data from the Transport General Authority to provide comprehensive information about railway transport, with the data being complete.

Accuracy and reliability 

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 

Timeliness 

GASTAT uses the Special Data Dissemination Standard (SDDS) issued by the International Monetary Fund. According to this Standard, all statistics agencies are required to publish data on an annual basis, and with a delay of not more than six months (180 days) after the end of the reference period. If the data are from different source, they may be published in a different frequency.

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

Comparability - geographical

Not applicable.

Comparability - over time 

Data is fully comparable.

Coherence- cross domain 

Not applicable. 

Coherence - sub annual and annual statistics 

Not applicable. 

Coherence- National Accounts 

Not applicable. 

Coherence - internal 

Railway Transport Statistics data have a complete internal consistency.

Data revision

Data revision - policy

Not applicable, only final results will be published.

Data revision - practice

Not applicable, only final results will be published.

Statistical processing

Source data

The Railway Transport Statistics publication relies on the administrative records of the Transport General Authority.
The main published variables from the administrative data source are:
•    Passenger traffic on railways.
•    Freight traffic on railways.
•    Railway infrastructure.

Frequency of data collection 

Annual.

Data collection

The data are collected from the administrative records in coordination with the relevant departments of the Authority for the management and collection of data, where the data of the publication of Railway Transport Statistics is obtained from the General Authority for Transport, which includes data on the number of flights, passengers and freight quantities in addition to statistical data for the railway transport sector.
The data is stored in the authority's databases after undergoing auditing and review processes following approved statistical methods and recognized quality standards. If errors or discrepancies are discovered, the data is cross-referenced with the data source for correction or clarification.

Data validation

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 publication's current year 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 Traffic and Transportation Statistics Department through modern technologies and software designed for this purpose.

Data compilation

Data editing:
Specialists of Traffic and Transportation Statistics Department have processed and analyzed data in this stage, and this step was based on the following measures:
•    Sorting and arranging data in groups or different categories in a serial order.
•    Summarizing detailed data into key points or data.
•    Combining many data segments and ensuring their interconnection.
•    Processing incomplete or missing data.
•    Processing illogical data.
•    Converting data into statistically significant data.
•    Arranging, presenting, and interpreting data.
A number of railway indicators were also calculated using spatial and statistical modelling:
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 modelling:
•    Combined railway data.
•    Calculation of railway density for governorates by administrative region.
•    Calculation of railway lengths.
•    Calculation of the density of the railway population by administrative region.
Output tables:
•    Railway network density of area by governorate and administrative region.
•    Density of the railway network of the population by administrative region.
•    Rail lengths.
Using the following equations:
•    Railway network density per capita by administrative region = length of Railway network in the administrative region / population of the administrative region.
•    Railway network density per square kilometer in the administrative area = length of the Railway network in the administrative area / area of the administrative area.

Adjustment

Not applicable, only final results will be published.