Production index for construction

Employees: Employees mean wage earners and active owners in the enterprise. A distinction is drawn between employees who are actually employed in the construction process and other employees. Contracted out labour, part-time employees, apprentices, holiday temps and others employed for shorter periods are included. Labour hired from employment agencies and enterprises in the construction industry, employees at subcontractors or employees on holiday, on strike, ill or laid off are not included.

Employees actually employed in the construction process : Covers manual workers and site operatives, including working foremen.

Hours worked : Productive hours worked by employees actually employed in the construction.

Indices are published by three types of construction works:

New building : Construction of buildings including site preparation, installation and completion work.

Renovation of building : Improvement, rebuilding, repair and maintenance. Renovation work, which includes addition or extension of a building, is to be classified as new building, if the addition/extension accounts for more than 50 per cent of the value of the project.

Civil engineering work : Transport infrastructure, pipelines, communication and electricity lines, complex constructions on industrial sites and sport recreation construction.

The index is compiled according to Nace Rev.2. Standard Industrial Classification SIC2007 .

Name: Production index for construction
Topic: Construction, housing and property

Division for Business Cycle Statistics

Index at national level.

Quarterly frequency. Published within 45 days after the end of the quarter.

Transmitted to Eurostat .

Data at the enterprise level are stored as text files on LINUX

The Production index is a volume index and measures the activity in building and construction industry. Since year 2000 it has been based on  working hours spent in the building- or construction site. Earlier a combination of building area and employment figures were used. The index goes back to 1st quarter 1995 and was first published in 1996.

Users of the statistics include Ministry of Finance, the Central Bank, Statistics Norway's national accounts division, international users and the construction industry.

No external users have access to the statistics and analyses before they are published and accessible simultaneously for all users on ssb.no at 8 am. Prior to this, a minimum of three months' advance notice is given inthe Statistics Release Calendar.

Principles for equal treatment

The indices are used directly in the quarterly national account.

The development of the production index is compared with the turnover in the annually structural business statistics or construction turnover.

The Statistics Act 21st of June 2019 number 32, §10 and §20

Council Regulation (EC) No. 1165/98 concerning short-term statistics. Regulation (EC) 1158/2005 of the European Parliament and of the Council amending CR No. 1165/98. Commission Regulation (EC) No. 1503/2006 implementing and amending CR No 1165/98 as regards definition of variables, list of variables and frequency of data compilation. Regulation (EC) 1893/2006 of the European Parliament and of the Council establishing the statistical classification of economic activities NACE Rev.2.

All activity in the construction industry section F except group 41.1 Development of building projects Standard Industrial Classification (SIC2007) . The observation unit was local Kind of Activity Unit (local KAU) until 2016 when the survey changed to collect data from enterprises.

The data for computing the index is obtained from two different sources: the Central Register of Local KAUs and Enterprises and a quarterly survey.

 A sample survey of about 2 000 units. All enterprises with more than 50 employees are included. Sub-samples are selected for enterprises with less than 50 employees, stratified according to detailed industry classification and size in terms of turnover. Enterprises with less than two employees are not included in the survey. About 1/4 of the enterprises with less than 50 employees are rotatied yearly.

This full sampling is new from  the 1st quarter of 2014.  Earlier the limit for full sampling was units with 20 and more employees.

The data is collected by postal survey at the end of the quarter, and the questionnaire can be filled out by Statistics Norway on Internet Altinn, Altinn.no. 

Controls include checking out the consistency in the values stated on the form, and the correspondence with values given the previous quarter. If a discrepancy is discovered, the respondent is contacted by phone or e-mail.

The production index is based on hours worked on construction sites as an input variable. The construction total index is calculated directly on the basis of total hours worked. The sub indices for building, renovation and civil engineering works are calculated by distributing the hours worked according to the number of persons employed in those types of work, given by the companies. The Quarterly sample data are grossed up to achieve assessments of total hours worked, using the ratio between the number of employees in the population and in the responding units. The series of hours worked are not modified with productivity factor. The index is chained annually upon rotation of the sample.

The production index is published as a volume index with the year 2015 as reference period.

The production index is adjusted for seasonal variations and for working days.

More information about seasonal adjustments .

What is seasonal adjustment?

Monthly and quarterly time series are often characterised by considerable seasonal variations, which might complicate their interpretation. Such time series are therefore subjected to a process of seasonal adjustment in order to remove the effects of these seasonal fluctuations. Once data have been adjusted for seasonal effects by a seasonal adjustment tool (SAS), a clearer picture of the time series emerges.

For more information on seasonal adjustment:   metadata on methods: seasonal adjustment

Seasonally adjusted series

For the production index, construction 5 seasonally series are published; Total, buildings and civil engineering works.

Not relevant.

From 1995 to 1998 the index for new buildings were calculated from a model based on new buildings started from the building register in the Matrikkel and the rest was based on employment-figures. In 1999 the figures from the Matrikkel was not used because of increasing reporting delay in the register. The calculation method was changed in 2000. From the 1st quarter of 2000, the calculation of the production index is based on measuring the number of hours worked. Earlier, the calculation is based on employment figures. The quarterly figures calculated after 1999 are therefore not directly comparable with the figures calculated before the 1st quarter of 2000.

Before the second quarter of 2004, contracted labour was not included. From the second quarter of 2004 labour hired from employment agencies was included. This was reversed in 2011 as it occurred that the companies omit to include contracted labour in their reports. Therefore, Statistics Norway will use other sources to estimate hours worked in construction industry by labour hired from employment agencies.

The data processing routines includes comprehensive control systems.

There will be a certain amount of non-response in form-based surveys such as the production index for building and construction. This is because some respondents either do not return their forms (total non-response) or return them incompletely filled out (partial non-response). Response rate at the expiration of the deadline is about 40 per cent. Following reminders it climbs to around 97 per cent. Total non-response is adjusted in the estimation procedure. By partial non-response the companies usually are contacted.

About 5 per cent of the units in the population are included in the sample survey. The sample overall coverage exceeds 55 per cent of the population in terms of employment. Gross margin ratio on subclass level shows some variation. For the 3rd quarter of 2007 a variation coefficient of 0.84 per cent was calculated.

Not relevant.