Central Statistics Office

Prices division

Central Statistics Office, Skehard Road, Cork, Ireland, T12X00E

House Price Index (HPI) gives comparable measures for changes in the prices of dwellings, both new and existing. It is quality adjusted and calculated according to a harmonised approach and a single set of definitions.

HPI is compiled separately for new and existing buildings at the national level. The total index is calculated using annually chain-linked Laspeyres method.

The index is based on all purchases of residential properties by household buyers at market prices

HPI sub-indices for the purchases of new and existing dwellings are compiled via hedonic regression using rolling time-dummy method. The main source of data is the stamp duty returns filed by the buyers of the residential property with the Revenue Commissioners. Detailed characteristics of dwellings, e.g. dwelling type, energy rating and floor area are obtained from the Building Energy Rating (BER) dataset provided by the Sustainable Energy Authority of Ireland (SEAI). Characteristics of the geographical area, where the dwelling is located, are obtained from the latest census data.

The HPI covers all market purchases of dwellings made by households regardless of their final use. The weights for the two sub-indices are equal to the total value of dwelling purchases for new and existing dwellings by households at market prices in the year Y-1, respectively. Both prices and weights include land plot value, as recommended by the Manual.

Purchase of residential property by household buyer at market prices

All purchases of residential properties by household buyers at market prices.

Republic of Ireland

Current HPI has been calculated from Q1 of 2010 to present. 

The HPI based on mortgage data from main banks existed from Q1 2005 to Q4 2009. It used different methodology and did not provide sub-indices for new and existing dwellings.

2015

Indices at Base: 2015=100

Reference quarter

HPI is produced under the REGULATION (EU) 2016/792 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 11 May 2016 on harmonised indices of consumer prices and the house price index

There is no national legal acts specific to the Irish HPI. However, the HPI is compiled under the general Statistics Act, 1993.

The stamp duty and building energy ratings data are provided to the CSO within the general framework of Statistics Act, 1993.

In addition, a special Memorandum of Understanding is signed with the Revenue Commissioners.

The data on all individual transactions of residential property is publicly available on the Property Services Regulatory Authority website: https://www.propertypriceregister.ie

Therefore, no specific confidentiality policy exists for HPI.

Not applicable.

Data is provided to Eurostat not later than at T+85 days after the end of the reference quarter.

National release calendar is published at https://www.cso.ie/en/csolatestnews/releasecalendar/

Check Eurostat website or access the national release calendar.

Indices are published via the Eurostat database and on the PxStat database of the Central Statistics Office.

Quarterly

Managed by Eurostat, there are no national press releases.

Eurostat database

National publication is available on the CSO website.

Eurostat database

National database

None.

None

There are no methodological documents specific to the HPI.

Numerous methodological documents exist for the Irish national counterpart (RPPI). These are available on the CSO's website:

https://www.cso.ie/en/methods/prices/residentialpropertypriceindex/

Numerous methodological documents, describing data sources, underlying concepts, matching, edits and hedonic regression models etc., are available for the Irish national counterpart of the HPI on the CSO's website.

No other documentation, specific to HPI is available.

General standards and guidelines are available at: http://www.cso.ie/en/media/csoie/releasespublications/documents/corporatepublications/standardsguidelinesqualityinstatistics.pdf

HPI methodology was revised in 2020 and is considered to be fully fit for purpose.

HPI fully responds to the needs formulated in the Regulation (EU) 2016/792

The publication of the HPI and user support are managed by the Eurostat.

HPI covers all statistics required by the relevant paragraphs of the Regulation (EU) 2016/792

Estimating the accuracy of the hedonic regression is difficult and was not done. No readily available measure currently exists.

Not applicable. The results are based on administrative data, which covers all transactions of residential property.

Hedonic regression requires the knowledge of precise dwelling type, energy rating and floor area. These are not available for all transactions, but only for those successfully matched to the BER data (about 75%).

Additionally, purchases of multiple dwellings in one transaction do not participate in the calculation of HPI (but are included in the weights), as prices and characteristics of the individual dwellings are not known in this case.

It is impossible to quantify the effects of the omission of the above on the accuracy of the HPI.

HPI is published nationally as part of the national RPPI, not later than at T+50 days after the end of the reference quarter.

HPI are transmitted to Eurostat within 85 days after the end of the reference quarter.

Weights are sent before 15 June of the year following the year to which the weights relate, as required by the Regulation.

Not applicable. HPI is calculated for the whole of the Republic of Ireland only.

The quarterly data is fully comparable from Q1 2010 to present. 

Quarterly and annual changes in the HPI resulting from the calculations are evaluated and compared to the information available from the media and industry experts. There are several commercial indices, mostly run by property advertising websites, based on asking prices. HPI results broadly agree with other available indicators, although the latter are mostly based on asking prices and direct comparison is impossible.

The overall HPI is calculated by annually chain-linked Laspeyres method from the sub-indices. Therefore, the results are fully coherent.

Direct costs amount to approximately 9 weeks of work by 4 staff members per quarter.

There is no additional respondent burden, as administrative data collected for other purposes is used exclusively for production of HPI. 

One quarter of HPI indices is revised every time to account for the transactions executed and filed in different quarters. The latest published quarterly data is, then, always preliminary.

Weights for the year Y are revised once in the reference quarter 1 of the year Y+1.

Full series of HPI was revised in 2017, due to availability of the new data from the Revenue Commissioners.

It was revised again in 2020, due to changes in methodology and again in 2022 to implement price-updating of the weights, as per regulation 2016/792.

No more revisions, apart from the regular updates of the latest quarter, are planned in the near future. 

See below.

The main data source is the stamp duty data compiled by the Revenue Commissioners and obtained by the CSO under Statistics Act, 1993. It contains the dates of execution and filing of the transaction, geographical address of the dwelling, the status of the dwelling (new/existing), the price of purchase, and some characteristics of the buyer.

Detailed characteristics of dwellings, e.g. type, energy rating and floor area are obtained from the Building Energy Rating dataset obtained from SEAI, which needs to be matched to the stamp duty data.

Detailed characteristic of the geographical area, where the property is located, such as deprivation index, are obtained from the latest Census of Population.

The source of information for the HPI weights is the same as for prices, the stamp duty dataset described above.

House Sales indicators are based on the stamp duty data described above.

Stamp duty data is collected monthly, BER data quarterly.

Electronically, by the secure transfer to the CSO's Administrative Data Center.

Various procedures ensure that errors are minimised in the data. The following validation checks are made on each record in the source data:

• Extreme values are identified, validated against external sources and edited, if thought necessary. This is essential to identify purchases of multiple properties in one transaction, which were not properly reported;

• Duplicate records are removed;

• A regression model is used to detect any remaining outliers. A total of around 5% of outlying records are removed each period.

See below.

See below.

HPI is a Laspeyres-type price index.

Quarterly indices for new and existing dwellings are produced by hedonic regression.

These are aggregated into the total HPI by using Laspeyres formula:

- Price relatives between current quarter and Q4 of year Y-1 are calculated for new and existing dwellings;

- Price relative for total HPI is calculated as arithmetic weighted average of the price relatives for new and existing dwellings;

- The value of HPI at current quarter is obtained by multiplying the HPI value at Q4 of year Y-1 by the calculated price relative. 

Weights are calculated at the beginning of each year based on the value of the relevant property transactions in the particular category during the year Y-1. 

Weights reference period is year Y-1, the weights are price-updated to Q4 of year Y-1. 

The chaining of the total HPI is achieved by applying the calculated price relatives for quarters of year Y to the HPI value at Q4 of the year Y-1.

Sub-indices for both new and existing dwellings are calculated using hedonic regression method.

HPI is calculated using hedonic regression, rolling time-dummy method, to adjust for the qualities of properties transacted in different periods and determine pure price changes.

The model is log-linear, using 4-quarter rolling window and log of the price as dependent variable. The input variables include: exact type of dwelling, geographical location,  building energy rating, floor area, and deprivation index of the area, where the property is located. 

Calculated price changes are applied to the sub-indices' values from the previous period to obtain the new values. Resulting 'raw' indices are additionally 'smoothed' by the double-exponential method.

Not used

Not used

See below.

Prices of dwellings are recorded at the execution date, i.e. at the transfer of ownership.

VAT is included in the price of new dwellings.

Taxes other than VAT are not included in the price of dwellings.

The HPI includes only transactions at market prices. As transactions which include government subsidies are normally below market prices, they are excluded from the HPI.

The price of land is included in both prices and weights.

Housing cooperatives are not very important for the Irish property market and are not marked on the source dataset. All market transactions by household buyers, where a stamp duty was paid, are included in the HPI.

The following types of property transactions are considered non-market and excluded from the HPI and House Sales indicators:

- Property exchanges and short-term leases (less than 100 years);

- Transactions, where a declared relationship exists between buyer and seller, e.g. relatives;

- Transactions, where the price is below €25,000, or marked as non-market by the Revenue Commissioners;

- Transfers between spouses, civil partners and cohabitants, based on the recorded claim of tax relief.

All other transactions are considered market and included.

Transactions including more than one property are treated as transfers of several identical units for the same price. For example, a transaction of N units for V euro will be treated as N units transferred at V/N euro per unit.

Multiple transaction are not used for calculating HPI, but are used for the weights and the House Sales indicators.

If there is a clear indication that several recorded transactions refer to the same property, e.g. the same address and the same seller/different buyers or the same buyer/different sellers, they are combined to represent one transaction with the aggregate price. 

If there is no clear indication, i.e. a single transaction with unique buyer and seller, it is treated as non-fractional, as there is no way to identify the partial transfer in this case.

Transactions of unusually high values are identified and investigated to determine, if they refer to a single dwelling or multiple objects. Multi-unit transactions are ruled out from the calculation of the HPI.

Additionally, outliers are determined by the regression and ruled out.

There is no grossing up or other adjustment for undercoverage to produce House Sales indicators. Administrative data is assumed to be complete.

The elementary indices are 'smoothed' using double-exponential Holt-Winters method.

None.