National Institute for Statistics (Istat)

Directorate for Business Statistics (DCSE)

Division for short-term business statistics (SED)

Via Tuscolana, 1788; 00173 Rome, Italy

Industrial production index (Indice della produzione industriale).

The survey describes the development of productive activity in Italy through the collection of production volumes.

NACE Rev.2.

Reporting unit: KAU or local unit KAU.

Observation unit(s): Unit of homogeneous production (UHP) or Local unit of homogeneous production (LUHP).

Target population corresponds to enterprises with 20 or more employees in 2015 for sections covered by this survey.  

Total number is about  30,000 enterprises.

Whole national territory.

The Industrial production survey was established in 1928. Series of indices with base 2015=100 start from January 1990.

The base year is 2015 starting from January 2018.

Index

Month

Legal basis

National level: This is one of the compulsory surveys fixed every year by a Decree of the President of the Republic (D.P.R.).

European level:

The legal basis for the STS indicators are the Regulation (EU) 2019/2152 of the European Parliament and of the Council on European business statistics, repealing 10 legal acts in the field of business statistics (EBS-Regulation) and the Commission Implementing Regulation 2020/1197 laying down technical specifications and arrangements pursuant to Regulation (EU) 2019/2152 (General Implementing Act).

Obligation on units to provide data: Surveys are mandatory. Penalties are foreseen for non-response.

Planned changes in legal basis, obligation to respond and frame used: None.

Not available

The release  calendar is disseminated on  ISTAT website: https://www.istat.it/en/information-and-services/journalists/press-releases-/press-calendar.

Monthly

Data are made available also through a statistical yearbook: Annuario Statistico Italiano (Italian version)

Before data dissemination, validated microdata are stored in the repository of the Institute, ARMIDA.
The repository ARMIDA (Archive of validated microdata) was established with the main objective of preserving and documenting the data produced by Istat surveys, and has subsequently supported the objective of disseminating data. The data archived in ARMIDA supplies, in fact, the different channels for the dissemination of microdata (for internal use at the Institute through the "Memorandum of access to microdata of ARMIDA, internal users ", for authorities in Sistan, for research files, for standard files, etc.).

A short description of the methodology and characteristics of the survey is contained in the technical explanatory note attached to the press release updated regularly.
Generally, major changes in methodology are announced a short period in advance in the publication Note Informative (last updating of the base year 2015=100 have been announced in the March 19, 2018 edition).

A description of methodology and sources used in preparing statistics is also contained in the Information System for Survey Documentation and Quality Control (Siqual); it is available on Istat's website. This system manages qualitative information related to each single phase of a survey's production process (SIQual).

More information about procedures applied for quality management and quality assessment in the document "Quality Guidelines For Statistical Processes" - December 2012

Essential points of Istat quality policy are: process quality, product quality, documentation, respect for respondents, strengthening of statistical literacy, users' orientation.

For more details: https://www.istat.it/en/organisation-and-activity/institutional-activities/quality-commitment

As regards main issues of quality, index is compliant with a good standard. Eurostat's requirements in terms of time series are fulfilled, timeliness is respected, cross-domain checks are used for monitoring a good level of coherence.

Some information on data quality are available in SIQual.

Main users of industrial production index are:

- Institutions: government departments, ECB, national central bank, international organisations, etc.
- Social actors: employers' organisations, trade unions, lobby groups, etc.
- Media
- Researchers & students
- Enterprises/businesses
- Internal users
- Eurostat

Not available.

Eurostat's requirements in terms of time series are fulfilled.

The samples are designed with the cut-off method and therefore sampling errors cannot be measured. Non-sampling errors are reduced or eliminated in the collection phase both using an electronic questionnaire that helps debugging and aiming at an increase of the response rate of enterprises.

It is not possible to compute sampling errors because a non-probability sampling method (cut-off) is used.

When the first provisional data are released, the weighted overall response rate was for the period 2019-2021 about 95,5%, even if for only year 2021 was 95% .
To speed up and increase the rate of response reminders and intensive follow ups by phone are addressed to the MIB (Main Industrial Business) units. These units are the most significant (in terms of production realised in the year before that of reference) for the specific products concerned.

The official release is published on average 40 days after the end of the reference period; data are transmitted to EUROSTAT within 40 days, using, when needed, an embargo clause; data are provisional at the time of the Press Release in which they are reported. They are then revised and become final after 3 years.

All releases delivered according to the timetable.

European definitions are used and they apply in the whole national territory 

Consistent time series data are available for a long period of time (since January 1990). When changes in source data, methodology and statistical techniques are introduced, historical series are reconstructed as far back as possible. 

Comparisons are made with the evolution of turnover and new orders indices. Results for these comparisons show good level of coherence for main aggregates.

Aggregates are always consistent with their sub-aggregates but for seasonnally adjusted data internal coherence could not be always ensured as direct method is used.

The cost estimate is compiled in terms of total number of hours worked (THW). It is equal to the product of three terms: (total) Annual Working Days (AWD), (total) Hours Worked per Day (HWD), Number of Persons involved in the Survey (NPS).

The burden estimate is compiled in terms of total number of minutes (TNM) taken to fill in the (web) questionnaire. The burden is applied to respondent, i.e. the person who fills in the questionnaire on behalf of the enterprise. To estimate it, two elements have been taken into account. The former distinguishes between beginner and expert respondent, to point out respectively the person who fills in the web questionnaire for the first time and the one who is familiar with filling in the form. The latter, closely concerns the information that have to be monthly provided. On average, by combining these two elements, the time spent to fill in the questionnaire (just the burden) is estimated in terms of total number of minutes between a minimum and a maximum threshold.

The general revision policy is predetermined and reasonably stable from year to year and is adopted in order to incorporate updated information. It consists of:

Routine revisions

1)     Monthly revision: indices referred to month m are revised after one month when indices referred to month m+1 are released. They take into account late respondents (estimated values for missing responses are replaced by reported figures) and correction from respondents.

2)    Once a year, in February, revisions of the last three years raw data is performed for improving indicators using information coming from enterprises and other source. In particurarly revision aims at incorporating three types of information into the indices available after the publication of the first revision. Specifically, the elements considered in the revision process are the following:

• Responses received from the enterprises after the dissemination of the revised indices (which usually occurs around 60 days from the end of the reference period); it involves a very limited number of responses, which accounts, on average, for approximately 1.7% of the sample (measured in terms of production volume) but which may determine corrections on the disaggregated indices.
• The ex-post corrections of information already received from the companies, and which, on the basis of successive verifications, result to be affected by errors in the measurement of the phenomenon. Usually these modifications have a minor effect on the aggregated indices, however they occasionally may cause significant revisions for specific sectors.
• The update and periodic revision of the short-term statistics (turnover index and hours worked), on which the used annual productivity coefficients are based, as previously mentioned, for the products indicated through the monthly flows of hours worked. These products, whose weight, as previously noted, is 13.1%, are concentrated in some sectors (particularly in machinery and mechanical equipment, electrical equipment and, specifically, transport vehicles, repairs and systems installation). As a consequence, the effect of the coefficient revision may be significant for those specific sectors.

Major revisions

Performed every five years, in correspondence of introduction of a new base year; they take into account new weighting systems, sample adjustments in enterprises and products lists.

At the time of each dissemination, users are informed whether data are preliminary or revised and the reason why data are revised (e.g. availability of additional data, major revisions declared by enterprises or other sources).
Generally, major changes in methodology, source and statistical techniques are announced in ad hoc publications. A detailed notification of methodological changes is also provided through seminars and papers disseminated throughout the scientific community. Non-scheduled revisions and major errors are published by specific notes.

Coherence of the revision policy is respected for data released nationally and transmitted to Eurostat.

A paragraph called ¿Revisioni¿ is attached to every press release in Italian. It contains a methodological note on revisions (revision policy, source, periodicity, etc.) and the results of the revision analysis for the current period presented. Major revision dues to mistakes are made known to the public after the event.
Exceptionally, the annual revision is disseminated through the bulletin released on January 2022 and concerns monthly indices of 2021. With regard to the unadjusted index, the annual growth rate was +12.1 for 2021, revised upward by 0.6 percentage points (from +11.5% to +12.1%).

The Mean Absolute Revision (MAR), Mean Revision (MR) and RMAR (Relative Mean Absolute Revision) are compiled for totals.

 
Details on revision policy are also available at the web page https://www.istat.it/en/economic-trends/revisions.

Data are collected through a statistical survey. In addition data are obtained:
¿ for electric energy, from TERNA (Rete Elettrica Nazionale);
¿ for mining and quarrying, from Uffici nazionali minerari, idrocarburi e geotermia (Ministero delle attività produttive);
¿ for manufacture of basic iron and steel and of ferro-alloys, from trade associations;
¿ for meat production, from the Istat survey on slaughtered animals for meat production.

The PRODCOM annual survey is used as frame.

Sample or census: The industrial production is a cut-off survey, with a non-probabilistic sample. For each product, enterprises are ranked according to the percentage of the value of production they represent for this product. Then the highest ranked units are drawn until 70% of the value of production is reached.

Criteria for stratification: not applicable

Threshold values and percentages: In total around 4,600 KAU are surveyed each month.

Monthly.

Self-administered data collection via electronic transmission, data are collected through a web portal called Portale Imprese https://imprese.istat.it/  Respondents need to login for insert data in the web questionnaire.

Estimates for non-response: For estimating non responses concerning a given product, usually an automatic estimation criterion is applied on the basis of the average percentage variation m/(m-1) calculated on responses available for the same product.

Estimates for grossing-up to population levels: None.

Type of index: Fixed-base Laspeyres index.

Method of weighting and chaining: The elementary products are aggregated up to the Class level using as weights the output value (from PRODCOM survey); the aggregation from the Classes up to the total is based on value added at factor costs weights drawn from SBS data.

Data are disseminated in unadjusted form, adjusted for working days (total index, indices by MIGs, branches at 4-digit level of NACE Rev. 2 classification), and in a seasonally-adjusted form.

The raw indices are trading days adjusted and corrected for seasonal effects by TRAMO-SEATS procedure, version 942 for Linux. Working days adjustment series and seasonal adjustement series are estimated down to 4 digit level. Adjustment models are completely reviewed at the beginning of each year (with the release of February data) and parameters are re-estimated every month. Each month, seasonally adjusted series are revised from January 2001.

A Reg-Arima approach is used for working days and seasonal adjustment. Calendar adjustment is performed by using our country specific calendar which also take into account national holidays. No calendar adjustment is performed where no significant effect is found. Leap year and moving holidays like Easter are adjusted.

Outliers (additive outliers, temporary changes, level shift) are manually fixed at the beginning of the year when seasonal adjustment models are revised. The critical value for the outlier detection and the filter length are automatically chosen, whereas model/filter selection is manual. Both additive and multiplicative seasonal adjustment decomposition are used.

Except for total consumption goods series, which is indirectly derived by weighted sum of non-durable and durable goods, all other series are directly adjusted. Whenever indirect adjustment is performed, a residual seasonality test is performed and checked.

None.