Documentation of statistics Volume index of industrial output
Basic data of the statistics
The indices of the most detailed industry level (3-digit level) of the volume index of industrial output are calculated by means of separate strata. Stratum 1 includes establishments of enterprises with more than 150 employees. Stratum 2 comprises enterprises with over 50 but fewer than 150 employees. Stratum 3 comprises enterprises with fewer than 50 employees. For enterprises with fewer than 50 employees, indices calculated from the Tax Administration's self-assessed taxation data are used in stratum 3 instead of own data collection.
Unit of measure
However, the volume index of industrial output also includes activities performed outside the borders of Finland. The biggest enterprises are asked monthly in the sales inquiry about sales of goods and services from abroad to abroad. The data may include merchanting if it is reported in the financial statement of an enterprise operating in Finland. The data of the sales inquiry do not fully cover the definition of global production in the national accounts. The quality of turnover has been examined as concerns the biggest globally operating enterprises but there is no fully clear picture of how well it covers global production.
The volume index of industrial output comprises sections B Mining and quarrying, C Manufacturing, D Electricity, gas steam and air conditioning supply in the Standard Industrial Classification 2008. Apart from a few exceptions, the sub-series of the main groups are also published at the 2-digit level of the standard industrial classification.
Frequency of dissemination
Accuracy, reliability and timeliness
The population comprises all manufacturing establishments and enterprises. All enterprises are included in industries using turnover. Statistics Finland's own data collection for the volume index of industrial output is based on a sample made of industries, which includes enterprises of industries with the biggest value added.
Data revision - practice
Model assumption error
In addition, missing data for the latest months are imputed in the calculation. These may cause error if the imputations differ much from the actual observation later on.
Comparability - geographical
Comparability - over time
Coherence - cross domain
Preliminary and final statistics are yearly published on structural business and financial statement statistics on the annual level. Preliminary data are completed in September of the year following the statistical reference year and final data in December.
The data of the statistics on industrial output describe production in Finland during the calendar year, while the data of the volume index of industrial output describe monthly data.
Coherence - sub-annual and annual statistics
Coherence -national accounts
Coherence - internal
The data of the statistics cannot be fully compared with other indicators of output in manufacturing because the industry coverage is different in the statistics on new orders in manufacturing, for example.
Source data and data collections
In some industries, the value and volume data of output are still inquired in the data collection of industrial output and enterprises are selected based on sampling. For these industries, data are also supplemented with the Tax Administration's self-assessed taxation data. The methodological description of the statistics describes in more detail what source data are used in which industry.
The web questionnaire of the volume index of industrial output has been tested in connection with its introduction and when changes have been made to it. In addition, the non-response rate of the inquiry is monitored monthly.
Frequency of data collection
Cost and burden
An inquiry on the response burden of the statistics was made in spring 2018. The average response time for the inquiry of the statistics was 56 minutes.
The calculation of the statistics is started by calculating changes in the output volume of the establishment or enterprise from the production data of individual establishments or enterprises' various commodities. This is done in order to produce an unambiguous figure from volume and value data that describes the development of the establishment or enterprise. Commodity-specific data are weighted together by using the value of production from the previous year as the weight for each commodity. Value data are deflated in this stage.
In the next stage of the calculation, stratum-specific volume change data are formed by industry. The data on enterprises belonging to different size categories described above are combined by weighting together the data on enterprises in a certain size category belonging to the same industry. Either the values of the output of enterprises or establishments or the weights calculated based on the sampling design are used as weights.
After this, stratum-specific data are weighted together to the 3-digit level of the industrial classification. The obtained change data are used to chain the previous year's index forward so that the actual final industrial index is obtained at the 3-digit level of the industrial classification. The strata are weighted by using gross value data available from the total data of the regional statistics on entrepreneurial activity for enterprises in the stratum corresponding to the size category of enterprises.
Calculation based on turnover indices
For some industries, the volume index is calculated by expressing at constant prices the turnover index of the industry concerned. The calculation of turnover indices is based on estimation of change. Data cannot be calculated directly by summing, because the data are incomplete for the latest months: only part of enterprises are included. Comparable observations for the examined month and for the corresponding month of the previous year are compared in the method by observing enterprise reorganisations and changes in reporting practices related to bookkeeping. The indices are recalculated monthly until the data are final. Methodological time series modelling has been used to aid in the calculation of the latest months’ indices. This reduces the revision caused by the slow accumulation of data. The most recent month of the statistics is released at a delay of around six weeks.
Formation of published industries and index calculation
The industry indices at the 3-digit level can be used to calculate aggregate indices that combine various sub-industries as weighted averages of industry indices. The weight used in aggregation is the value added of the industry calculated from total data.
In Finland, the volume index of industrial output is calculated as a chain index with variable weights where the weight structure used in calculation is updated annually. The benefit of continuous updating is that the statistics reflect the structural changes in manufacturing as quickly as possible. The drawback is, for example, that the index point figures may become revised nearly two years backwards.
Although the index has no fixed base year, the data are published relative to a certain selected reference year for which the average of the indices of the original series is 100. The reference year is 2018 starting from the data for January 2018. The index point figures of earlier years have also been made comparable with the indices of the current reference year (2015=100).
Validation of data of own data collection for the volume index of industrial output
The data are checked in every calculation round on the unit level by going through the most significant changes and deviating observations.
Validation of data based on turnover indices
The database based on the Tax Administration's data and Statistics Finland's sales inquiry is updated continuously. Systematic error types have been detected in certain variables, which are corrected even before the calculation. Due to data updates such as accumulation of data or changes in enterprises' monthly data, the calculated indices may change slightly from one calculation period to another. In the calculation stage of the indices, observations that prove to be erroneous are corrected or removed. The data are checked in each calculation round at the enterprise level against information about the most significant business reorganisations and changes in turnover, and enterprise openings and closures.
The revisions are examined in connection with the review process at the micro and macro levels. The special characteristics of different industries are also taken into account when the data are validated.
The data of the volume index of industrial output are published as industry-specific index series. In addition to original series, indices are calculated as working day adjusted series and seasonally adjusted series as well as trend series.
By means of working-day adjusted indices, percentage changes can be calculated between different years by comparing the same months in different years. Changes within a year can be monitored by means of seasonally adjusted series and trend series. When using seasonally adjusted series and trend series it should be noted that in the Tramo/Seats method the latest months are partly based on model-based forecasts, so particular caution must be used in conclusions made based on them.
Further information about seasonal adjustment can be found in the methodological description of the statistics and in the report on seasonal adjustment with the Tramo/Seats method on Statistics Finland's home page.
Documentation on methodology
Principles and outlines
Contact organisation unit
Legal acts and other agreements
Statistics Finland compiles statistics in line with the EU’s regulations applicable to statistics, which steer the statistical agencies of all EU Member States.
Further information: Statistical legislation
Only the necessary data that are not available from administrative data sources are collected from data suppliers. Confidentiality is taken into account when data are published and it is ensured that the data or development of a single enterprise cannot be deduced on the basis of the results. The volume index of industrial output is one of the so-called sensitive statistics whose data can be treated before publication only by persons separately named by virtue of the Act on the Openness of Government Activities (Section 24, Paragraph 1, Sub-paragraph 13). The results are not released to users before the official date of publication of the statistics.
Confidentiality - policy
Further information: Data protection | Statistics Finland (stat.fi)
Confidentiality - data treatment
Industries 19, 20, 21, 22, 26, 27, 29 and 30 are not published separately because they contain dominant enterprises. They are published as combined industries and they are included in the figures for total industries (TOL BCD).
The data are submitted to Eurostat as confidential or flagged if there are three or fewer units on the publication level.
Further information: Publication principles for statistics at Statistics Finland
Accessibility and clarity
In addition to statistical data published in the StatFin database, a release on the key data is usually published in the web service. If the release contains data concerning several reference periods (e.g. monthly and annual data), a review bringing together these data is published in the web service. Database tables updated at the time of publication are listed both in the release and in the review. In some cases, statistical data can also be published as mere database releases in the StatFin database. No release or review is published in connection with these database releases.
Releases and database tables are published in three languages, in Finnish, Swedish and English. The language versions of releases may have more limited content than in Finnish.
Information about changes in the publication schedules of releases and database tables and about corrections are given as change releases in the web service.
Data revision - policy
The reason why data in statistical releases become revised is often caused by the data becoming supplemented. Then the new, revised statistical figure is based on a wider information basis and describes the phenomenon more accurately than before.
Revisions of statistical data may also be caused by the calculation method used, such as annual benchmarking or updating of weight structures. Changes of base years and used classifications may also cause revisions to data.
Seasonally adjusted data in statistics on economic trends become revised because of the calculation method used. Additional information on a new time series observation is exploited in model-based calculation methods and this is reflected as changes in previous releases. Revisions of the latest figures to be seasonally adjusted are elaborated on in the releases and quality reports of statistics.
A summary table of the revisions that have taken place is also published in connection with key statistics on economic trends and some annual statistics. The table shows how the data for the statistical reference periods have changed between the first and the most recent statistical release.
Annual comparisons are made with the data of the statistics on industrial output.
Quality management requires comprehensive guidance of activities. The quality management framework of the field of statistics is the European Statistics Code of Practice (CoP). The frameworks complement each other. The quality criteria of Official Statistics of Finland are also compatible with the European Statistics Code of Practice.
Further information: Quality management | Statistics Finland (stat.fi)
Data are released to all users at the same time. Statistical data may only be handled at Statistics Finland and information on them may be given before release only by persons involved in the production of the statistics concerned or who need the data of the statistics concerned in their own work before the data are published.