Statistics Poland

Trade and Services Department

00-925 Warszawa, al. Niepodleglosci 208

The House Price Index (HPI) measures the evolution of market prices of all residential properties that are purchased by households, independently of its previous owners or final use.

There are used the following classifications:

1. type of dwellings (new and existing dwellings)
2. geographical area (16 voivodships, of which capital of voivodships for new flats and the biggest cities in voivodships for existing flats)
3. number of rooms (up to 2 rooms, 3 rooms, 4 rooms and more).

Household sector

The HPI measures the price evolution of dwellings purchased by households. Calculations of HPI for Poland are based on information on flats (single-family houses are excluded). It covers transactions made by household regardless of its final use. This index thus covers not only the transactions that are new to the household sector but also all that are traded between households. Index figures are based on market prices, non-market prices are excluded from the HPI. Data are compiled on the basis of full transaction prices (final market prices paid by households) which are collected through the use of an administrative data source. Transaction prices include the value of land. All transactions are included (both cash and mortgage). The HPI is a chain-linked Laspeyres-type price index.

A market transaction of a residential property purchased by a private household.

The target population is the set of all transactions of dwellings purchased by households.

HPI covers the whole territory of Poland. It is compiled for the country as a whole, 16 voivodships (NUTS2, except breakdown inside of Mazowieckie Voivodship) and selected cities.

Data are available since the first quarter 2010.

The HPI reference period is 2015=100.

Data are presented as indices and growth rates.

The compiled quarterly indexes represent the whole calendar quarter.

European level:

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, and repealing Council Regulation (EC) No 2494/95 (OJ L 135, 24.5.2016, p. 11–38)

Commission Implementing Regulation (EU) 2023/1470 of 17 July 2023 laying down the methodological and technical specifications in accordance with Regulation (EU) 2016/792 of the European Parliament and of the Council as regards the house price index and the owner-occupied housing price index, and amending Commission Regulation (EU) 2020/1148 (L. O. 181, 18.7.2023)

National level:

The Law on Official Statistics passed on 29th June 1995 with subsequent amendments.

"Programme of Statistical Surveys of Official Statistics" which exists as an annual regulation of the Council of Ministers.

The Law on Real Estate Management passed on 21st August 1997 with subsequent amendments.

Not applicable for HPI

National legislation:

All statistics collected and published by the Statistics Poland are governed by the Law on Official Statistics passed on 29th June 1995 with subsequent amendments (unified text published in the Journal of Laws 2021 No. 955). The question of confidentiality is explained in the art. 10 and 38 of the Law on Official Statistics:

Article 10: "The collected and gathered in the statistical surveys of official statistics individual and personal data shall be confidential and subject to particular protection; the data shall be used exclusively for statistical calculations, compilations and analyses and for the creation by the statistical services of official statistics sampling frames for statistical surveys conducted by those services; providing or use of individual and personal data for other than specified above purposes shall be prohibited (statistical confidentiality)."

Article 38: "1. It shall not be allowed to publish or disseminate individual data obtained in the statistical surveys of official statistics.

2. It shall not be allowed to publish or disseminate obtained in statistical surveys of official statistics statistical information which can be linked or can identify natural persons or individual data characterizing business entities, especially if the aggregated data consist of less than three entities or the share of one entity in the compilation is higher than the three-fourths of the total.

3. In the case of business entities, information and statistical data mentioned in point 2, can be published if the person authorised to represent particular entity gave consent to publish specific data considering economic and financial results of the entity."

European legislation:

Regulation (EC) No 223/2009 of the European Parliament and of the Council, of 11 March 2009, on the transmission of the data subject to statistical confidentiality to the Statistical Office of the European Communities.

The Regulation (EU) 2015/759 of the European Parliament and of the Council of 29 April 2015 amending Regulation (EC) No 223/2009 on European statistics was published in the Official Journal of the European Union on 19 May 2015.

Confidential data are treated in accordance with the policy described in concept 7.1.

An official release calendar is published on the website of Statistics Poland. A release calendar is established for the given month, for the given quarter as well as for the whole year.

An official release calendar is available on the website of Statistics Poland.

Data are disseminated to all users via internet. Publication dates are announced in advance in an official release calendar.

According to Article 14 of the 'Law on Official Statistics' the official statistics shall provide to all equal, indiscriminatory and simultaneous access to the statistical information.

Quarterly.

HPI indices for the country as a whole and for 16 voivodships (NUTS 2 level, except breakdown inside of Mazowiecki Voivodship) are published:

• in the Official Journal of the Republic of Poland 'Monitor Polski' in the form of an announcement of the President of the Statistics Poland (only in Polish).
• as Price indices of residential premises ( https://stat.gov.pl/en/latest-statistical-news/)

The HPI indices are published in:

• Statistical Bulletin (Tabl. 1)
• Concise Statistical Yearbook of Poland - Households. Dwellings
• Statistical Yearbook of the Republic of Poland - Prices

The HPI indices are disseminated in Knowledge Database Prices - Real estate prices 

Micro-data are not disseminated.

Not available.

The basic information on surveys conducted by the Statistics Poland is given in the 'Programme of Statistical Surveys of Official Statistics'. A short description of the HPI is available on the website of Statistics Poland. There is an internal documentation which describe the methodology of compiling HPI indices. The applied methodology was developed taking into account Eurostat recommendations and specifically recommendations included in the 'Technical Manual on Owner-Occupied Housing' as well as in the 'Handbook on Residential Property Prices Indices'.

A quality report was prepared in 2015. It was elaborated on the basis of standard quality procedures recommended in the ESS Handbook for Quality Reports. The quality of the survey was described by means of standard quality indicators characterizing the following quality aspects: relevance, accuracy and reliability, timelines and punctuality, comparability and coherence.

Documentation on procedures applied for quality management is available on the website of Statistics Poland.

The legal basis of the quality policy of the Polish official statistics is the internal Regulation of the President of Statistics Poland (No 35 of 28th December 2011) on measurement, evaluation and monitoring of statistical surveys quality.

The applied quality policy is based on the follwoing international and european standards:

• Fundamental Principles of Official Statistics
• European Statistics Code of Practice
• Quality Assurance framewor QAF
• Regulation (EC) No 223/2009 of the European Parliament and of the Council of 11 March 2009 on European statistics

For measurement and assessment of the quality of statistical surveys, the following tools are applied:

• standard quality reports
• standard quality indicators
• self-assessment checklist
• audits/peer reviews

In order to assure an appropriate quality of HPI indices automatic quality controls have been implemented within the HPI production process, in order to detect and correct errors in the data that are received. Outliers, such as dwellings with particularly small or large floor area or very high or low prices per m2 are excluded from the index.

Self-assessment based on the OOH Technical Manual and the European Statistical System (ESS) definition of quality is routinely carried out.

Classification of national data users with an indication of their importance for official statistics, taking into account the purpose of data usage, is the following:

• key users - government and self-government administration, National Central Bank, Polish Financial Supervision Authority;
• important users - research institutes, universities, organizations of employers, enterprises, insurance institutions, media;
• other users - social organizations, professional self-government, economic self-government, trade unions, students, individuals.

User needs are systematically monitored and taken into consideration while drafting the 'Programme of Statistical Survey of Official Statistics' for the next year. The organs of the state power, government and self-government administration, organizations of employers and other institutions, provide opinions on statistical surveys and recommend implementation of the new ones. Data users, e.g. universities, research institutes, enterprises or individuals may indicate their needs by data inquiries and orders.

The last user satisfaction survey was conducted at the end of 2013. The survey covered the following data users: government and self-government administration, National Central Bank, Polish Financial Supervision Authority, research institutes, universities, organizations of employers, enterprises, insurance institutions, media, social organizations, professional self-government, economic self-government, trade unions, students, individuals. The survey was carried out via internet. For this purpose, an electronic questionnaire has been elaborated and was placed on the CSO server. Questions included in the questionnaire have been adjusted to all data users mentioned above and they comprised, among others, the following issues:

- general information on using statistical data (which data were used, how often and for what purpose),
- assessment of data availability, transparency, timelines, comparability and level of details,
- evaluation of services provided by the CSO and assessment of the internet website www.stat.gov.pl,
- assessment of statistical metadata (methodology, glossaries, classifications applied, etc.),
- users needs and expectations concerning disseminated statistics and offered services,
- general assessment of statistics (according to the European Statistics Code of Practice).

HPI for Poland is based on information on flats (single-family houses are excluded).

The accuracy of the HPI indices depends on the quality of the used data source and the applied methodology. The accuracy of HPI indices is considered to be sufficient. The main deficiencies are connected with timeliness of recording data in the used data source and the lack of information on the floor space area of the structure in case of houses.

Sampling errors are not calculated for HPI indices because the survey is not based on random sampling. The aim of the survey is to collect information on all transactions concluded in the surveyed period. However due to time lag between the transaction date and its registration in the administrative database not all transactions are taken into account in calculations.

In general the used data source is assessed as suitable to portrait the evolution of actual transaction prices as experienced by buyers and sellers. However it has some limitations which have impact on obtained results. One of the main problems is lack of information on the floor space area of the structure in case of houses. Consequently the HPI for Poland is based only on information on flats.

Moreover the following non-sampling errors can occur in the survey of HPI:

• errors due to non-response,
• data entry errors,
• quality change bias.

In order to minimize the impact of errors in data provided by respondents on HPI indices appropriate validation procedures are applied. In case of non-response a telephone and e-mail follow-up of non-respondents takes place. In case of missing data imputation procedures are applied. In order to control changes in the mix of properties sold the stratification method is used.

HPI is published quarterly about 95 days after the end of the reference period. The dates of HPI publication (Price indices of residential premises) are publicly available.

HPI figures are provided to Eurostat on a quarterly basis, about 85 days after the end of the reference period. HPI weights for 2023 was transmitted in the same time as HPI figures for Q1 2023.

HPI indices for different geographical areas of Poland are comparable.

HPI indices are comparable over time.

The HPI categories: H.1.1. Purchase of newly built dwellings and H.1.2. Purchase of existing dwellings are conceptually comparable with the OOH categories: O.1.1.1.1. Purchases of newly built dwellings and O.1.1.2. Existing dwellings new to households. However the HPI does not follow the net acquisition concept and the price of land is included in prices and weights.

The HPI indices are cross-checked with data compiled by the National Central Bank (average prices per square meter and existing stock hedonic house price indexes for 16 capital cities of voivodships). The indices compiled by Statistics Poland and the NCB show similar trends.

HPI indices are internally coherent. Concepts, definitions and classifications for compiling the indices are consistent across all subdivisions. Higher-level aggregates are obtained from lower-level indices with the use of well-established procedures.

For 2023, estimated employment cost amounted to about EUR 113,400 for 2023 (of which EUR 24,400 for HPI calculation and EUR 89,000 for preparing administrative data for HPI calculation).

Administrative data are obtained for free on the basis of the annual Statistical surveys program of official statistics. Administrative data sources are used to minimize the burden on respondents.

The HPI data is not subjected to periodic and systematic revisions.

HPI data from 2010Q1 to 2015Q1 were revised and sent to Eurostat in October 2015. The revision was carried out due to introduction of the HPI breakdown to new and existing dwellings.

See below.

The HPI indices are compiled using administrative sources called "Register of Real Estate Prices". Data are provided by 380 district governors offices (local administration units).

HPI weights are based on actual dwelling transaction values. The partition of the total HPI weight into new and existing dwellings is done using information available from the same source as used for prices, i.e. administrative sources called "Register of Real Estate Prices".

The House Sales indicators are compiled using administrative sources called "Register of Real Estate Prices". Data are provided by 380 district governors offices (local administration units) about 6 months after reporting year.

Data collection is carried out on a quarterly basis.

Reporting units provide electronic data in the three formats of files (SWDE,  GML and GML with  the new data structure) via electronic system of data collection. The files are checked as regards format correctness and then converted into database format. In case of non-response, any errors in files or problems with data completeness respondents are contacted by e-mail or phone.

Data provided by reporting units are subject to quality checks. Among other things the following checks are performed:

• response rate,
• correctness of the file format,
• data completeness (time coverage of provided data, number of transactions in comparison with previous periods), 
• correctness of used symbols, - checks of consistency between varables,
• detection of missing values,
• detection of duplicated records,
• errors detection, 
• outlier detection (with the use of the algorithm based on interquartile range),
• visual data inspection.

In case of missing data imputation procedures are applied.

All non-market transactions are excluded from calculations.

See below.

See below.

HPI is a Laspeyres-type price index.

The HPI indices have been aggregated using weights based on market transaction values.

The HPI indices at the lowest level have been calculated using the ratio of the arithmetic mean of transaction prices.

The HPI weights are based on the value of market transactions in the previous year both for new and existing flats where the buyer is a natural person are taken into account. The land component is included. The weights are updated annually and recalculated into prices of the 4th quarter of the previous year.

HPI for 2023 are calculated on the basis of the market transaction value which took place in 2022.

Weights are price updated to the fourth quarter of the year t-1.

The HPI is chained on a yearly basis using the fourth quarter of the previous year as the linking period.

In order to reduce the 'quality mix' problem the stratification method is applied. 

Not applicable.

Not applicable.

For HPI computing 498 strata (of which 157 strata for the new flats and 341 strata for existing flats) are used.

The following stratification variables are used:

1. type of dwellings (new and existing dwellings)
2. geographical area (16 voivodships, of which capital of voivodships for new flats and the biggest cities in voivodships for existing flats)
3. number of rooms (up to 2 rooms, 3 rooms, 4 rooms and more).

See below.

The price of the dwelling is the price in the notarial deed signed at the time when the ownership is transferred.

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. Sales of social dwellings to sitting tenants (usually at a large discount) are excluded from the index compilation.

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

Housing cooperatives are not covered in the HPI.

Non-market transactions are excluded.

Multi-object transactions are identified by the same transaction number. If multi-object transactions include both residential and commercial premises, residential premises are included only.

In order to avoid double counting some transactions, in which the spouses are the purchasing party, are excluded. It takes place when such transaction is registered as two separate sale transactions of the same real estate (two records in the database) and share ½ is assigned to each of them.

Outlier detection  is carried out for each stratum by using the algorithm based on interquartile range.

Not applicable

No adjustments other than quality adjustment are applied to the HPI data.

None.