Content
About the statistics
Definitions
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Name and topic
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Name: Construction cost index for road construction
Topic: Prices and price indices
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Next release
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Responsible division
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Division for Housing, Property, Spatial and Agricultural Statistics
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Definitions of the main concepts and variables
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The CCI measures the changes in the prices of input factors to the construction process of residential buildings. CCI ignores gains in productivity and changes in profit margins
Labour cost is 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.
A Laspeyres price index is a price index where the weights remain fixed. A chained Laspeyres price index is an index linked by Laspeyres indices with different sets of weights.
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Standard classifications
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Price: Actual sales prices to the construction industry. Price on the 15th of the mid-month in the quarter exclusive VAT.
Administrative information
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Regional level
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National level only
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Frequency and timeliness
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Quarterly
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International reporting
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Not relevant
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Microdata
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Quarterly price observations for goods and services are stored on UNIX.
Background
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Background and purpose
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The construction cost index measures changes in input prices for road constructions.
The cost indices ignore gains in productivity and changes in profit margins. Statistics Norway has published construction cost indices for civil engineering works since 1985. The weights are renewed in 2004. At the same time the former construction cost index for water plant is put down. The types of construction covered are open air road, concrete bridge and rock tunnel.
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Users and applications
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The indices are used to regulate the costs of construction works. At Statistics Norway the CCI (Construction cost indices) is used as deflator in the National Accounts.
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Equal treatment of users
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Not relevant
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Coherence with other statistics
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Not relevant
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Legal authority
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Statistics Act Sections 2-2 and 2-3
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EEA reference
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Not relevant
Production
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Population
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Construction cost indices measures the price developments of material, labour, transport, plant and other types of input factors in civil engineering works, i.e. costs incurred by the contractor/producer carrying out the construction work. It is two different types of information to be collected about the input factors, the percentage of each component (weights) and the prices. The weights are compiled every fifteenth year through cost studies of civil engineering works. The prices are measured quarterly.
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Data sources and sampling
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Price data of materials are obtained from the following price indices in Statistics Norway:
Construction cost index for residential buildings Consumer Price Index Price index of first-hand domestic sales The labour costs are based on Statistics Norway's quarterly wage statistics and a percentage of social security charges according to wages.
Machinery costs indices calculated by NTNU
Transport costs indices compiled by Statistics Norway.
In addition some material, service and machinery prices are obtained exclusively for this statistics by means of questionnaires.
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Collection of data, editing and estimations
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Some material, service and machinery prices are collected quarterly by means of questionnaires.
The prices are put through tests, which identify observations with large price changes from the previous quarter. 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.
The construction cost index is calculated as a Laspeyre Index with fixed weights. The fixed weights are derived from project data collected from tenders and calculations, and accounting data from highway authorities.
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Seasonal adjustment
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Not relevant
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Confidentiality
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Not relevant
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Comparability over time and space
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Statistical releases older than 5 July 2017.
It is breach in time series in the first quarter of 2004, in connection with compilation of new weights.
Accuracy and reliability
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Sources of error and uncertainty
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The outlets might, for the sake of convenience, copy the previous month's prices instead of the correct prices when 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.
For some goods price measurements are based on price lists, and changes in discounts given to building contractors are not taken into account. Other errors:
Price effects due to changes in relative prices, or the price ratio between different goods and services has been changed over time. Unsatisfactory handling of quality changes.
Statistics Norway has not initiated separate calculations of the impact of these measuring errors in the building cost indices.
Each month about 1 per cent off all questionnaires is missing. Missing prices are imputed. The imputations are based on the average changes in prices from the previous month of the same product.
Sampling errors are not calculated
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Revision
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Not relevant