Statistics Norway

Division for housing, property, spatial and agricultural statistic

Statistics Norway, Box 1400 Rasta,2225 Kongsvinger, Norway

Name of indicator/source

Construction cost index for residential buildings.
Construction cost index for residential buildings, material.
Construction cost index for residential buildings, labour cost.

NACE Rev. 2.

Activities covered: The index covers residential buildings and is based on two types of buildings, namely detached houses and blocks of flats.

Size classes covered: Not relevant.

List and definition of variables: The CCI measures the changes in the costs of input factors to the construction process of residential buildings. CCI ignores gains in productivity and changes in profit margins. The cost elements are, material costs, labour cost, machinery costs, transportation costs and other costs.
Material prices are actual prices to the construction activity, excluding VAT.
Labour costs are divided into two main components, which are calculated separately: wages and salaries for actual worked hours, and other labour costs. Other labour costs include wages and salaries for hours not worked and social security charges.

Planned changes in information collected: None

Accounting conventions: The data refers to the 15th of the month.

Reporting unit:The reporting unit is the local KAU.

Observation unit(s):Not relevant.

A sample of 300 suppliers to the construction industry (mainly wholesale companies) provides about 2000 price observations every month.

Geographical area covered: All regions of Norway are covered.

Date of first use as a source: The index has been published since 1978.

Base (reference) year: 2015

The material prices are collected by means of questionnaires, which are sent to the suppliers to the construction industry (mainly wholesale companies). The labour costs are based on Statistics Norway's quarterly Labour cost index, based on full cencus data from a-meldingen. Machinery costs indices calculated by NTNU. Transport costs indices compiled by Statistics Norway.

Reference year of this report: 2015

Legal basis: The Statistics Act, Sections 2-2 and 2-3.

Obligation on units to provide data:Mandatory according to the Statistics Act.

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

Not relevant.

Dissemination of terms and conditions under which official statistics are produced, including confidentiality of individual responses:

Information about how the statistics are produced is given as About the statistics at the website. This applies to - among other things - information about collection methods, explanation of terms and information about sources of errors.

Treatment of confidential data:Not relevant.

Advance dissemination of release calendar: The publication schedule is pre-released in Statistics Norway's Advance Release Calendar.

See planned releases at: http://www.ssb.no/en/kalender

Simultaneous release to all interested parties:Statistics Norway releases statistics at its website, www.ssb.no. The statistics are released at 08:00 in Norwegian and English.

Identification of internal government access to data before release:No other governmental or non-governmental bodies have prior access to data before its release.

Transmission to Eurostat and further use of the statistics:Data are transmitted electronically to Eurostat within minutes after publication on the Internet.

Monthly

Identification of ministerial commentary on the occasion of statistical releases:None

Name of national paper publications:In 2006 a paper publication containing results and methodology on Construction Price Indices and House Property Price Indices were published, see
http://www.ssb.no/english/subjects/08/02/30/nos_d372_en/nos_d372_en.pdf

Name of national electronic dissemination:Data are published on the Internet at http://www.ssb.no/bkibol_en/

On the home page to the article connected to the statistical release there is also a link to statbank. http://www.ssb.no/en/table/08651

Not relevant.

Planned changes in national dissemination methods:None.

Dissemination of documentation on methodology and sources used in preparing statistics:

Documentation on methodology and sources used in preparing statistics are published on the Internet at http://www.ssb.no/bkibol_en/ ("About the Statistics"). The methodology is also described in an own publication about Construction Price Indices and House Property Price Indices, see
http://www.ssb.no/english/subjects/08/02/30/nos_d372_en/nos_d372_en.pdf

Description of standard tables produced:

There are two standard tables published:
— construction cost index for detached houses of wood;
— construction cost index for multi-dwelling houses.
These tables present a total of 7 types of building works, each divided by two indices, one for total costs and one for materials.

The overall index for residential buildings is divided in labour costs and material costs. No regional breakdown is available.

The prices are put through tests, which identify observations with large price changes from the previous month. Price are also checked when sorted by item and when items are aggregated into groups. Sub-indices and item-indices are checked against timeseries that are published earlier and comparisons with other statistics.

Summary description of quality criteria calculated for national purposes:The prices are put through tests, which identify observations with large price changes from the previous month. Prices are also checked when sorted by item and when items are aggregated into groups. Sub-indices and item-indices are checked against time-series that have been previously published.

Not available

The CCI is used to regulate the cost of construction works. At Statistics Norway the CCI is used as deflator in the National Accounts.  

Consulting choice for building and construction

To be filled in.

The outlets might, for the sake of convenience, copy the previous month's prices instead of the correct prices whwn filling out the questionnaires. The most obvious cases of this kind are revealed in a manual check carried out when receiving the questionnaires. When a product or service is no longer sold the outlets are instructed to find a replacement and mark it in the questionnaire. If they fail to do so, the difference in price between the old product and the replacement will incorrectly be registered as a price change of the old product. 

Skewness: the sample of goods and services is updated every fifteenth year. In addition products are replaced if an outlet no longer deliver this particular product.

Non-responce: Each month about 1 pr cent off all questionnaires are missing. Missing prices are imputed. The imputatuons are based on the average changes in prices from the previous month of the same product.

Sampling errors are not calculated.

Response rate: Response rate is 95%.

Actions to speed up or increase the rate of response:

For some goods prices measurements are based on price lists, and changes in discounts given to building contractors are not taken into account.

Price effects due to changes in relative prices. The price ratio between different goods and services has been changed over time.

Unsatifactory handling of quality changes. Statistics Norway has not initiated separate calculations of the impact of these measuring errors in the building cost indices. 

Timeliness:The construction costs index for residential buildings is published approximately 12 days after the end of the reference month.

Timetable of data collection:The prices are measured monthly. The questionnaires are sent to the units on the 15th of each month, and returned to Statistics Norway 10 days later.

No time lag between the actual delivery of the data and the target date.

The index is published at national level only.

The index goes back to 1978.

Dissemination of information that support statistical cross-checks and provide assurance of reasonableness:None

Confrontation with other data sets:None.

Some data are collected from the Consumer Price Index, Wage Statistics, Cost Index for Road Goods Transport and NTNU's Cost Index for Machinery.

An outlet uses an average of 17.5 minutes every month to fill out the questionnaires, which means that the sample of outlets use a total of 1 050 hours or 131 days of work each year.

We produce no prelimenary data.

The same revision policy applies nationally and in transmissions to Eurostat

Provision of information about revision and advance notice of major changes in methodology:

Revisions are announced simultaneously with the release of the indices.

No planned or unplanned revisions for the statistical process that is subject of this report.

Type of source:The material costs are collected by a statistical survey. Other sources are Statistics Norway's quarterly wage statistics adjusted for the social security charges, and further machinery costs indices calculated by NTNU and transport costs indices compiled by Statistics Norway.

Frame on which the source is based:Central Register of Establishments and Enterprises.

Sample or census:A sample of 200 suppliers of the construction activity (mainly wholesale companies) provide about 2000 price observations every month.

Criteria for stratification:Stratification by activity, turnover, geography and judicious selections.Threshold values and percentages:Not available.

Frequency of updating the sample:Every second year.

Periodicity of data collection: Monthly.

Questionnaires used in the survey:A single standardied electronically questionnaires are used to collect material costs

Planned changes in national questionnaires:None

Data collection media:Electronically

Planned changes in data collection methodology:None.

The prices are put through tests, which identify observations with large price changes from the previous month. Prices are also checked when sorted by item and when items are aggregated into groups. Sub-indices and item-indices are checked against time-series that are published earlier and comparisons with other statistics.

Estimates for non-response:Not relevant.

Estimates for grossing-up to population levels:No grossing-up is done.Type of index:The indices are calculated according to a Laspeyres formula within a fixed base.

Method of weighting and chaining:The weights are based on calculations and accounting data from 13 representative apartment building projects and 4 detached house projects using projects completed in 2015. The weight basis was prepared in accordance with the Norwegian Standard for specification of costs in building projects and adopted in September 2019. The overall building cost index for houses comprises the two indices for detached houses and apartment buildings. The weights used are square metres of useful floor space for dwellings under construction multiplied by the average price (in Kroner) per square metre.

Planned changes in production methods:None

WDA, SA and other calculations:No seasonal adjustments are made.

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