Methodology and Quality Update

Latest Update on Methodology and Quality

2026/06/25

Statistical Presentation

Data description

The Annual Industrial Production Index (IPI) presents annual statistical indicators that measure the relative changes in the production volumes of economic activities included in the industrial activities compared with the base year and is considered one of the key statistical outputs of the Industrial Production Survey.
The Industrial Production Survey is conducted to collect data on the main characteristics as follows:
The Industrial Production Survey includes the collection of periodic data from establishments operating within the targeted industrial activities in accordance with the National Classification of Economic Activities (ISIC4). These activities include mining and quarrying; manufacturing; electricity, gas, steam, and air conditioning supply; and water supply, sewerage, waste management and remediation activities, thereby ensuring comprehensive statistical coverage of the industrial sector.
Key objectives of the survey:

• Compiling the IPI.
• Showing the changes in production over time, which can be used to forecast future trends.
• Facilitating international comparisons.

The data is used to calculate:

• General Industrial Production Index.
• IPI by the National Classification of Economic Activities (ISIC4).
• IPI by main economic activities.
• The annual change rate in the General IPI.
• The annual change rate in the indices by the National Classification of Economic Activities (ISIC4).
• The annual change rate in the indices by main economic activities.

Classifications

The following classifications are applied in the Industrial Production Survey.
National Classification of Economic Activities (ISIC4):
It is a statistical classification based on the International Standard Industrial Classification of All Economic Activities (ISIC4), used to describe the economic activities of an establishment. 
Saudi Product Classification - based on the Central Product Classification (CPC 2.1): 
The Saudi Product Classification based on the Central Product Classification (CPC 2.1) issued by the United Nations Statistical Commission in 2018 is an approved standard for the aggregation and classification of products, including goods and services. This classification is used in areas such as industrial production, national accounts, international trade, and the balance of payments to support the harmonization of statistics and facilitate statistical comparisons.
The classifications are available on GASTAT's website:  www.stats.gov.sa

Statistical concepts and definitions

Terms and concepts of the Industrial Production Survey:

• Annual Industrial Production Index (IPI):
  It is an annual economic indicator that reflects the relative changes in the average volume of industrial production quantities during the year compared with the base year, based on data from the Industrial Production Survey, which is conducted on a sample of industrial establishments operating within the targeted industrial activities, namely mining and quarrying; manufacturing; electricity and gas supply; and water supply, sewerage, waste management and remediation activities.
• Annual change rate:
  An index that reflects the relative changes in industrial production volumes during the target year compared with the previous year and is used to measure the annual growth or decline rate in industrial production.
• Production:
  It is the process through which inputs, such as raw materials and production factors, are transformed into outputs of industrial goods within a specified period of time.
• Goods:
  Tangible industrial products resulting from the production process, which are tradable or intended for final or intermediate use.
• Quantity:
  The volume of actual output of the produced good during the reference month, measured using the appropriate unit of measurement according to the nature of the product (e.g., tons, kilograms, liters, units, and cubic meters)
• Value:
  The monetary value of the total production sold during the reference month, excluding tax.
   

Data sources

The Annual Industrial Production Index Publication relies on two main data sources: 
First source: Monthly Industrial Production Survey.
It is the main data source through which monthly data are collected from the targeted industrial establishments to measure the volume of industrial production, and are then used to derive and calculate the Annual Industrial Production Index indicators.
Second source: Administrative (register-based) data.
These are data derived from the administrative records of the relevant entities, including

• Ministry of Energy.
• Ministry of Environment, Water and Agriculture.
• Ministry of Industry and Mineral Resources.

These data are used for the purpose of calculating the index.
Key indicators published for the survey data are:

• General index of industrial production.
• IPI by the National Classification of Economic Activities (ISIC4).
• IPI by main economic activities.
• The annual change rate in the General IPI.
      The annual change rate in the indices by the National Classification of Economic Activities (ISIC4).
• The annual change rate in the indices by main economic activities.

Designing the data collection tool

The Annual Industrial Production Index relies on data from the monthly Industrial Production Survey, and no separate data collection tool is designed for it. Therefore, the questionnaire used in the monthly survey is considered the primary data collection tool from which the data required to calculate the annual index are derived.
Accordingly, this section presents the data collection tool for the monthly Industrial Production Survey, as it represents the approved methodological framework for collecting the data used in producing the annual industrial production indicators.
Data are collected through a questionnaire developed and designed by specialists at the General Authority for Statistics (GASTAT). The design process took into consideration international recommendations, standards, and definitions. The questionnaire was also shared with relevant entities to obtain their feedback and observations. The questions were formulated in a specific scientific manner to ensure the standardization of the question wording used by field researchers. An electronic questionnaire was designed using the Computer-Assisted Personal Interviewing (CAPI) method to ensure ease of use by field researchers, along with the Computer-Assisted Telephone Interviewing (CATI) method to contact respondents by phone, as well as providing the option of conducting Computer-Assisted Web Interviews (CAWI).
Questionnaire sections:

• Section one: Basic establishment data, including the main identification information and the determination of the main economic activity conducted by the establishment according to the National Classification of Economic Activities (ISIC4).
• Section two: Monthly production data on the goods produced by the establishment during the reference period, according to the Saudi Classification of Products. 

Editing and validation rules:

Editing and control rules were included in the questionnaire to ensure the consistency, accuracy, and reasonableness of the collected data. These rules were designed by establishing logical relationships between responses, questions, and various variables to assist the field researcher in directly detecting any errors during data entry.
To ensure the quality of the Industrial Production Index data, review and validation rules were established, as follows:

• Error rules:

  These are rules that cannot be bypassed during the data entry process, where the researcher is required to modify the data by referring back to the data provider to verify their accuracy, and there are (8) rules.

• Warning rules:
  These are rules established to verify the accuracy of the data entered by the researcher. The field researcher may bypass them if they confirm the accuracy of the data, with a total of (7) rules.
  Administrative data are collected using standardized data request tables directed to the data-owning entities to obtain periodic, harmonized, and documented data derived from administrative records relevant to the Industrial Production Index indicators, thereby ensuring improved data quality and integration across the different data sources.

Questionnaire test (cognitive test)

The outputs of the previous cognitive testing were relied upon, and there was no need to repeat the test this year. The interview sample consisted of a random sample of establishments, and the cognitive test was conducted on several questionnaire questions based on the cognitive testing pillars. Some observations were identified regarding the following pillars: the overall concept of the question, clarity of question wording, clarity of the terms used in the question, and the appropriateness of the response options, leading to the preparation of a report providing a comprehensive summary of the cognitive testing results.

Statistical population

The statistical population of the Industrial Production Survey consists of all industrial establishments operating within the specified industrial economic activities in accordance with the adopted classification (ISIC4), which conduct actual production activities in the Kingdom of Saudi Arabia.

Sample Design

The Annual Industrial Production Index relies on the data collected from the monthly Industrial Production Survey. It uses the same approved sample frame applied in the monthly survey, which was designed based on the Cut-off Sampling method, as the survey focuses on industrial establishments with the highest relative importance. The sample size of the Industrial Production Survey is 1,004 establishments. 

Statistical unit

The statistical unit used is the establishment.

Data collection

Industrial Production Survey data are collected monthly through:
First: Data collection from respondents (survey).
Data for the Industrial Production Survey are collected from the targeted establishments using approved electronic data collection systems,
including

• Computer-assisted Telephone Interviews (CATI).
• Computer-assisted Web Interviews (CAWI).
• Computer-assisted Personal Interviews (CAPI).

These systems enable direct data entry into the central databases, enhancing data recording accuracy and processing speed.
Second: Data collection from administrative records:
Administrative data are obtained from the relevant entities through approved official channels, in accordance with data exchange mechanisms. These data are used to support statistical coverage and complete some industrial activities. The quality of the administrative data is verified by comparing the data with the available historical series and reviewing significant differences with the data-providing entity when needed.
Several automated validation procedures are applied during the data collection process to ensure data quality. This includes verifying the completeness of mandatory fields, checking internal consistency between variables, testing values to ensure they fall within expected ranges, and detecting any potential duplication or inconsistencies in the data. Electronic data collection systems also rely on automated validation rules and alerts, in addition to conducting subsequent reviews in accordance with the approved statistical standards, before the final approval of the data.
It should be noted that the Annual Industrial Production Index does not rely on an independent data collection mechanism; rather, it is derived from the data collected as part of the monthly survey using the same channels and tools.

Data collection frequency 

The data collection process for the Industrial Production Survey is conducted on a monthly basis, where the monthly data are subsequently used to produce the annual statistical indicators of industrial production. 

Reference area

The Industrial Production Survey covers 13 administrative regions in the Kingdom of Saudi Arabia.

Reference period (time reference)

Reference period of the variables or dataset is as follows:

• The reference period for the monthly index data represents the calendar month preceding the survey implementation period.
• As for the Annual Industrial Production Index, its reference period is the calendar year 2025, as it is derived from the monthly data covering all months of that year.

Base period

The base year used to calculate the Industrial Production Index is 2021.

Measurement unit

Statistical indicators are presented as index numbers relative to the base year, in addition to annual change rates expressed as percentages.

Time coverage

The Annual Industrial Production Index indicators are available from 2021 to 2025.

Publication frequency

The Industrial Production Index indicators are primarily published on a monthly basis, while the annual indicators are issued annually after completing the monthly data for the entire reference year.

Statistical processing

Error detection

The Annual Industrial Production Index relies on the processing applied to the data from the monthly Industrial Production Survey. Accordingly, this section presents the statistical processing applied to the monthly survey, considering it the basis for producing the annual indicators.
Methodological procedures are applied to detect missing inputs, outliers, and data deviations, based on standardized validation rules and approved statistical methods, to ensure the completeness, accuracy, and consistency of the data before the analysis stage.
These processes include the following:

• Identification of illogical or out-of-range values.
• Tabulation of data and verification of its accuracy, with reference to the primary data source, when any errors or observations related to data quality are identified.
      Review of internal consistency between variables to ensure logical relationships
• among values.
• Comparison of current data with previous data to ensure the consistency of time series prior to data processing and the extraction of final results.

Data integration and matching from multiple sources 

Industrial Production Index Statistics rely on the integration of data from multiple sources, including administrative records and survey data, with the aim of achieving coherence between data characteristics and components and enhancing the comprehensiveness and accuracy of the indicators.
The integration process is carried out according to methodological steps that begin with harmonizing definitions, classifications, and reference periods across the different sources, followed by matching and linking processes using unified identifiers or approved linking keys. Verification procedures are also conducted to ensure data consistency after integration. These include checking consistency between variables, reviewing conflicting values, and verifying the structural integrity of the data.
This procedure aims to ensure the reliability and accuracy of the final data used in preparing the statistical publication and to provide a clear and consistent representation of the state of Industrial Production Statistics.

Imputation and calibration

The Annual Industrial Production Index relies on the processing applied to the data from the monthly Industrial Production Survey. Accordingly, this section presents the statistical processing applied to the monthly survey, considering it the basis for producing the annual indicators.
The data derived from the different sources are reviewed by identifying missing and outlier values. Values are considered outliers when significant unjustified changes occur in production quantities compared to the previous period. In such cases, establishments are contacted to verify the validity and accuracy of the data before any imputation is applied. 
Standard imputation methods are also applied, based on international practices included in the United Nations Statistical Commission’s Manual on the Industrial Production Index, ensuring data completeness and the reliability of the indicators. 
The indicators are calculated using the Laspeyres methodology, based on base-period weights. This methodology allows for an accurate measurement of economic performance over time, taking into account the impact of larger and more heavily weighted sectors on the overall index. 

• : Product price in the base period.
• : Production quantity in the base period.
• : Production quantity in the comparison period.
• : Relative weights.

The annual Industrial Production Index indicators are derived from the monthly index series, where the annual average of the monthly index values during the reference year is calculated, reflecting the average change in the volume of industrial production compared to the base year.

Seasonal adjustments

No seasonal adjustment methodology is applied to the Industrial Production Index data, as the actual values are adopted as they are without removing or adjusting for potential seasonal effects.

Adjustment of preliminary results 

Not applicable, as the annual Industrial Production Index indicators are considered final upon their release. They are calculated after the completion of the monthly series for the reference year and are not subject to revision except in cases of comprehensive methodological updates, such as a change of the base year.

Resources used

Quality dimensions

Suitability

A criterion that indicates the extent to which the product meets users' needs.

User needs 

Internal users of Industrial Production Index results within GASTAT:

• National accounts.

External users and beneficiaries of Industrial Production Index results:

• Government entities.
• Regional and international organizations.
• Research institutions.
• Media.
• Individuals.

Key indicators that external users benefit from:
 

Completeness 

The data of the Industrial Production Index are considered complete and cover all targeted economic categories according to the National Classification of Economic Activities (ISIC4), including mining and quarrying, manufacturing, electricity, gas, steam and air conditioning supply, and water supply; sewerage, waste management and remediation activities, ensuring comprehensive statistical coverage in accordance with international standards. Results are also published at detailed levels up to the second-digit level.

Accuracy and reliability 

A criterion that indicates the extent to which calculations or estimates are close to the accurate or true values that reflect reality.

Overall accuracy 

• Data quality is enhanced through the selection of researchers based on several practical and objective criteria related to the nature of the work and their qualifications and training.
• Alert, validation, and correction rules are applied during data collection via the Industrial Production Survey's electronic questionnaire to enhance data quality.
• The data is examined against previous years to identify any significant changes.
• The internal consistency of the data is verified.
• The links between variables are checked, and coherence between different data series is confirmed.

Timeliness and punctuality 

Timeliness: A standard that indicates the length of time between the availability of information and the occurrence of the event.
Punctuality: It reflects the time lag between the data publication date and the target date when publication actually occurs.

Timeliness 

The results of the Annual Industrial Production Index are published after completing the data for all months of the reference year and any updates made to them, in accordance with the approved statistical release schedule. The release of the results is carried out annually within a period not exceeding six months (180 days) from the end of the reference year.

Punctuality 

The publication is carried out according to the release dates in the published statistical calendar for the Annual Industrial Production Index on GASTAT’s website. 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 Industrial Production Index Statistics are internationally comparable, as they are produced in accordance with the International Standard Industrial Classification of Economic Activities (ISIC Rev.4) and in accordance with the approved international standards. The index is calculated and published at the overall level of the Kingdom of Saudi Arabia, reflecting changes in industrial production at the national level.

Comparability - over time 

The survey started in 2016 as a quarterly survey, and the time series of the Industrial Production Index has undergone several methodological updates during the covered period:

• Change in survey frequency:
  In 2019, the survey transitioned from a quarterly to a monthly frequency, enabling more detailed and timely data coverage.
• Base year update:
  In 2024, the base year was updated to (2021=100) to more accurately reflect the updated industrial structure, ensuring better representation of the current economic sectors.
• Annual releases of the Index: 
  The annual publications of the Annual Industrial Production Index were introduced to provide annual indicators on the performance of the industrial sector. These publications are prepared based on the monthly index series by calculating the annual average of the monthly index values during the reference year. The annual publications of the Index were first issued from the 2024 reference period.

Coherence- Cross domain

Not applicable, as the Annual Industrial Production Index represents an annual average of the previously published monthly indices and is not considered an independent statistical product that can be assessed for its consistency with other related statistics.

Coherence- Sub-annual and annual statistics 

The Industrial Production Index is issued on a monthly and annual basis, where the annual index is calculated based on the average of the monthly index values. The results show methodological consistency between the monthly and annual releases, as both levels rely on the same data source and statistical methods, with a difference in the level of temporal aggregation.

Coherence- National Accounts 

Industrial Production Index results generally reflect consistency with national accounts, as the Industrial Production Index is considered one of the key inputs used in national accounts.

Coherence- Internal 

Industrial Production Index estimates have full internal consistency, as they are all based on the same set of detailed data and are calculated using the same estimation methods.

Accessibility and clarity

Accessibility of data for users and the availability of accurate or aggregated data. It also indicates the availability of the methodology and quality report.

News

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 at the link: 
Press release

Publications

GASTAT issues the Annual Industrial Production Index publications regularly in accordance with a pre-prepared release plan, and they are published on GASTAT's website.  The Authority is keen to disseminate its results in a manner that serves all types of users, including publications in various formats that contain dissemination tables and charts for data and indicators, the Methodology and Quality Report, and the questionnaires used, in both Arabic and English.
The results of the Industrial Production Index are available at:
Industrial Production Index

Online database

The data is published on the statistical database:
Statistical database.

Microdata accessibility

Not available.

References and standards

The Industrial Production Index is based on the International Recommendations for the Index of Industrial Production (2010) issued by the United Nations Statistics Division, which provide the basic standards and principles for calculating the index in an internationally consistent manner.
International Recommendations for the Index of Industrial Production (2010)

Quality assurance

GASTAT is committed to the following principles: Impartiality, ensuring that the statistical product is user-oriented, quality of processes and outputs, efficiency of statistical processes, and reducing the burden on respondents. 
Data are validated through quality procedures and controls implemented at various stages of the statistical process, including data entry, data collection, and other final controls.

Quality assessment

GASTAT carries out all statistical activities in accordance with the National Model (Generic Statistical Business Process Model (GSBPM)). During the comprehensive evaluation phase, which is the final phase of the GSBPM, information collected throughout each phase and sub-process is used to prepare an evaluation report summarizing all quality-related challenges associated with each statistical process. This report serves as an input for improvement and development procedures.

Confidentiality

Confidentiality - Policy

According to Royal Decree No. 23 dated 07/12/1379, 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.

Data processing confidentiality

Data are presented in right tables in order to summarize, understand, as well as extract their results to compare them with other data, and to obtain statistical significance about the selected study population. Moreover, referring to such data presented in tables is much easier than going back to check the original questionnaires, which may include some data such as individuals' names and addresses, establishments’ names, and data providers' names, which violates the confidentiality of statistical data.
“Anonymity of data” is one of the most important procedures. To keep data confidential, GASTAT removed information related to individuals, households, or business entities in such a way that the respondent cannot be identified either directly, such as by name, address, contact number, identity number, commercial registration number, etc., or indirectly by combining different characteristics that are particularly rare among respondents, such as age, occupation, education, etc.

Dissemination policy

Statistical calendar

The Annual Industrial Production Index has been included in the statistical calendar.
Statistical Calendar

User accessibility

One of GASTAT’s objectives is to better meet its clients' needs; therefore, it provides them with the results of the Annual Industrial Production Index Publication as soon as they are released.
GASTAT also receives clients' questions and inquiries regarding the publication and its results through various communication channels, such as:

• GASTAT’s official website: www.stats.gov.sa
• GASTAT's official email 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).