Production in Building and Construction Index

Introduction of updated series with base year 2015=100

The Production in Building and Construction Index (PBCI) provides monthly statistics on output in the sector. The index monitors trends in the value and the volume of production in building and construction. The index is primarily intended to function as a short-term indicator. For long term analysis, the annual Building and Construction Inquiry is recommended.

The principal difference between the value and volume indices is that the value index measures changes in the value of work done while the volume index tracks the quantitative volume of production by excluding the effect of price changes using a price deflator. The Capital Goods price index for Building and Construction is used as the price deflator for this series.

This series is also available using the interactive tables in PxStat, the CSO’s Main Data Dissemination Service.

Reference Periods

The PBCI is carried out on a monthly basis and this data is published nationally by quarter.

Base Year

The set of indices, based on the Laspeyres Index, has been compiled with reference to base year 2015=100. The underlying structural weighting system for the output categories (Residential Building, Non-Residential Building, and Civil Engineering) is based on the annual Building and Construction Inquiry, which provides Building and Civil weights, combined with the new Dwelling Completions data to generate Residential weights. The sample for the index is stratified by size class based on number of persons employed: A (0–4), B (5-19), C (20-99) and D (>99). Size class weights were produced using the Building and Construction Inquiry 2015 and the Quarterly National Household Survey Q2 2015.

Legal Basis

The Quarterly Survey of Construction (QSC) is carried out in accordance with S.I. No. 446 of 2023 Statistics (Monthly Survey of Construction) Order 2023, made under the 1993 Statistics Act. The statistics are also required for EU comparisons under Council Regulation (EC) No. 2019/2152 which has been amended by Regulation (EC) No. 1893/2006 with the introduction of NACE Rev. 2.

Scope and Coverage

The PBCI covers, on a sample basis, the production of all firms in the private (i.e. non-State) sector whose main activity is building, construction, or civil engineering i.e. firms classified to division F of the Statistical Classification of Economic Activities in the European Community (NACE Rev. 2). Approximately 1,500 firms are surveyed monthly.

Seasonal Adjustment

Seasonal Adjustment is conducted using the direct seasonal adjustment approach. Under this approach, each individual series is independently adjusted. Each individual seasonally adjusted series is calculated based on working day adjusted data.

The seasonal adjustments are implemented using the X-13-ARIMA methodology. This is applied using the Win X-13 software package, developed by the U.S. Census Bureau. This methodology estimates seasonal factors while also taking into consideration factors that impact on the quality of the seasonal adjustment such as outliers and level shifts in the series.

Additional information on the use of X-13-Arima see Monsell B. C., Lytras, D., and Findley, D. ‘Getting Started with X-13 ARIMA SEATS Input Files’, March 2016.

Methodology

A description of the methodology is available within the Methods area on the CSO website located here.

Comparison with other national series

There are differences (due to timing, definitions and other factors) between the quarterly and annual trends measured by this survey and by other national data sources. In particular the quarterly series from the PBCI shows considerable volatility. Table A, below, compares the main annual results of the survey with national employment and house building indicators. 

The series shows a decrease of 4.7% in the annual volume of production in building and construction between 2022 and 2023. In the same period, employment in the sector, as measured by the Labour Force Survey, rose by 0.6%.

For residential buildings, the PBCI shows a decrease of 10.2% in the annual volume of production between 2022 and 2023. The New Dwellings Completions series shows an increase of 9.8% in the same period.

Data on house-building commencements are also included in Table A. This indicator shows an increase of 21.7% in residential building in 2023 when compared with 2022.