Central Bank of the Republic of Türkiye (CBRT)

Data Governance and Statistics Department, Surveys and Indices Division

Saray Mah. Küçüksu Cad. No: 64/B Ümraniye İstanbul/TÜRKİYE

Dwelling prices indicated in valuation reports prepared at the time of approval of individual housing loans are used as a proxy for price. Valuation reports which form a basis for housing loans are prepared by real estate appraisal companies. The actual sale of the property and utilization of the loan is not required and all dwellings appraised are included in the scope.

Following indicators are produced on a monthly basis:

Residential Property Price Index (RPPI)

Residential Property Price Index for New Dwellings (NRPPI)

Residential Property Price Index for Existing Dwellings (ERPPI)

Unit Price

Nomenclature of Territorial Units for Statistics (NUTS): Regional unit classification designed for the whole country in compliance with the European Union Regional Statistics System to develop a comparable statistical database.

Level: Regional units formed according to NUTS.

• NUTS Level 3: 81 regional levels corresponding to cities.
• NUTS-Level 2: 26 regional levels formed by combining NUTS-Level 3 units.

Nomenclature of Territorial Units for Statistics (NUTS) is used for aggregating the data. The data are aggregated at the 3^rd and 2^nd levels of NUTS respectively for RPPI and ERPPI and the overall indices for Türkiye are constructed using the data aggregated at the 2^nd level. NRPPI is constructed using the data aggregated at the 3^rd level and the index for Türkiye is constructed using the data aggregated at the 3^rd level.

Household sector.

Residential Property Price Index (RPPI): Residential property price index constructed using hedonic regression method in which prices are adjusted for quality changes related to observed housing characteristics.
Residential Property Price Index for New Dwellings (NRPPI): Price index constructed using hedonic regression method for dwellings built in the current and the previous years covering the whole country.
Residential Property Price Index for Existing Dwellings (ERPPI): Price index constructed using hedonic regression method for the dwellings built before the current and the previous years covering the whole country.

Unit Price: Price calculated by dividing the value of a property by its gross area of use.

Appraisal values of dwellings.

The target population is the set of valuations of all types of dwellings prepared by real estate companies.

The RPPI and ERPPI, which are constructed to represent the whole country, cover appraised dwellings in 74 cities. While constructing the NRPPI, which also represents the whole country, data pertaining to the valuations of new dwellings in 51 cities where there are sufficient number of observations are used.

The national RPPI, ERPPI and NRPPI are weighted averages of the regional indices. RPPI is published for the whole country and on the basis of NUTS Level 2, whereas NRPPI and ERPPI are published for the whole country and for the three major cities. 

Data are available from January 2010.

2017=100

Following units are used:

Index figures with reference to the year 2017
Annual and monthly percentage changes
Unit prices in national currency (Turkish Liras)

Relevant month.

Article 43, CBRT Law No. 1211, as amended on April 25, 2001 by the Law No. 4651
Turkish Statistics Law No. 5429 - Official Statistics Program

Not applicable.

Article 43, CBRT Law No. 1211, as amended on April 25, 2001 by the Law No. 4651
Turkish Statistics Law No. 5429 - Official Statistics Program

Not applicable.

The release calendar is announced to the public in advance and published on the first business day of each year on the website of the CBRT.

Release calendar is available on CBRT webpage.

The institutions and organizations which are the subscribers of the data delivery system are informed about the publication of the results just after they are made available on the website of the CBRT.

Monthly.

Online press releases are available on the website of CBRT

Not available.

Online database: EVDS

Not available.

Not available.

Methodological paper can be found at CBRT webpage. ( A Hedonic House Price Index for Turkey, Timur Hülagü, Erdi Kızılkaya, Ali Gencay Özbekler, Pınar Tunar, 2016)

Not available.

All data are checked for completeness and consistency with statistical concepts and definitions. Automatic quality controls have been implemented within the RPPI production process in order to detect and correct errors in the data files that are received. Outliers, such as dwellings with very high or low unit prices and mass valuations are excluded from the index.

Not available.

Policy makers; Commercial banks; Real estate appraisal companies; Economic analysts.

The “Statistics Users Survey” is conducted in order to monitor users' needs.

Since transaction data have quality issues, indices are produced based on appraisal data. Quality of transaction data could be improved and indices could be produced based on transactions.

Not available.

Not available.

Not available.

Indices are published approximately 45 days after the end of the reference month.

Indices are sent to Eurostat within 45 days after the end of the reference month.

RPPI and ERPPI data are comparable across NUTS 2 regions while NRPPI data are comparable across NUTS 3 regions.

Data are comparable over time.

Other data relating to the housing market are obtained from internet advertisements. Index derived from this data set is used for internal reports and shows the same trend as the RPPI.

Due to different weight source and coverage (see 3.7.) RPPI is not calculated by taking weighted average of NRPPI and ERPPI. RPPI has an independent calculation process, thus RPPI does not always move between NRPPI  and ERPPI (see 18.5.1. for detailed information).

OOHPI for Türkiye is not available.

Estimated annual cost for production of RPPI is approximately 150,000 EUR in total.

Due to late and/or revised submission of valuation reports, indices may be subject to revision up to one year.

RPPI data are revisable. Unperiodic revisions which stem from methodological changes are announced in advance.

See below.

Administrative data is used to compile the RPPI.

Data on house sales registered by the General Directorate of Land Registry and Cadaster (LRC) and average value of dwellings which are included in the CBRT dataset are used as weights for aggregating the strata in constructing the RPPI and ERPPI whereas building occupancy permit statistics issued by TURKSTAT and average value of dwellings are used for weighting in computing the NRPPI.

Not available.

Data are collected monthly.

Data are obtained by electronic databases.

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 and eliminated,
• Data cleaning is done to remove cases of obviously erroneous data,
• Minimum and maximum values are investigated,
• Mass valuations are identified and eliminated.

See below.

See below.

RPPI, ERPPI and NRPPI, which measure quality adjusted price changes are computed by estimating the regression coefficients for each period and each stratum. RPPI is not calculated by taking weighted average of indices for new and existing dwellings. Each of them has an independent calculation process. Indices are computed with the base year 2012 (2012=100) in the pre-2017 period and 2017 (2017=100) starting from 2017. The whole series are computed with the base year 2017.

Price indices for individual stratum used in the aggregation procedure compare the current period prices to the average prices of whole 2017. Nomenclature of Territorial Units for Statistics (NUTS) is used for aggregating the data. The data are aggregated at the 3rd and 2nd levels of NUTS respectively for RPPI and ERPPI and the overall indices for Türkiye are constructed using the data aggregated at the 2nd level. NRPPI is constructed using the data aggregated at the 3rd level and the index for Türkiye is constructed using the data aggregated at the 3rd level. Data on house sales registered by the General Directorate of Land Registry and Cadastre (LRC) and average value of dwellings which are included in the CBRT dataset are used as weights for aggregating the strata in constructing the RPPI and ERPPI whereas building occupancy permit statistics issued by TURKSTAT and average value of dwellings are used for weighting in computing the NRPPI. Weights used to produce the RPPI and ERPPI are updated each year with the weights calculated using the average value and number of dwellings sold in the related stratum in the previous year. In calculating the indices for the very first years of the series, 2010 and 2011, data on average value of dwellings for 2010 and dwelling sales data for 2011 are used as an exception. Building occupancy permits issued in the two consecutive years preceding the reference year and previous year’s average value are used to calculate the weights for constructing the NRPPI. In calculating the weights for 2010, data on average value of dwellings for 2010 are used as an exception.

Data on house sales registered by the General Directorate of Land Registry and Cadaster (LRC) and average value of dwellings which are included in the CBRT dataset are used as weights for aggregating the strata in constructing the RPPI and ERPPI whereas building occupancy permit statistics issued by TURKSTAT and average value of dwellings are used for weighting in computing the NRPPI. Due to different weight source and coverage (see 3.7.) RPPI is not calculated by taking weighted average of NRPPI and ERPPI. RPPI has an independent calculation process, thus RPPI does not always move between NRPPI  and ERPPI.

Weights used to produce the RPPI and ERPPI are updated each year with the weights calculated using the average value and number of dwellings sold in the related stratum in the previous year. In calculating the indices for the very first years of the series, 2010 and 2011, data on average value of dwellings for 2010 and dwelling sales data for 2011 are used as an exception. Building occupancy permits issued in the two consecutive years preceding the reference year and previous year’s average value are used to calculate the weights for constructing the NRPPI. In calculating the weights for 2010, data on average value of dwellings for 2010 are used as an exception.

Weight reference period is t-1. Thus, there is no need to update the weights.

No chaining is applied

Hedonic method combined with geographical stratification approach is applied to produce RPPI, NRPPI and ERPPI

RPPI, NRPPI, ERPPI which measure quality adjusted price changes related to the observed housing characteristics are constructed by using Laspeyres variant of the average characteristics hedonic method and log-linear regression model. The log-linear regression models are applied for each stratum and for each period which enables observing the price effects of quality component changes by stratum and in time.
Dependent variable: Logarithm of appraisal value
Independent variables: Gross area of use, quality of construction, year of construction, number of bedrooms, number of bathrooms, number of balconies, security service, heating, elevator, parking lot, swimming pool

Not available.

In the scope of the current RPPI, ERPPI and NRPPI implementation, in which the geographical stratification approach is applied, 211, 211 and 89 homogenous strata are used respectively.

See below.

Dwelling prices indicated in valuation reports prepared at the time of approval of individual housing loans are used as a proxy for price.

VAT is included in the price of new dwellings.

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

Not applicable.

The price of land is neither included in prices nor in weights.

Housing cooperatives are not covered in the RPPI.

"Non-market" transactions are not covered in the RPPI.

Multi-object transactions are not covered in the RPPI.

Fractional transactions are not covered in the RPPI.

The Tukey’s Hinges method has been implemented in the analysis of extreme values in order to construct the indices.

Unit prices that qualify the following equation:

m2 unit price < Q1-3*(Q3-Q1) or m2 unit price > Q3+3*(Q3-Q1)

where Q1: Lower Quartile and Q3: Upper Quartile are accepted as extreme values and excluded from the analysis.

Not applicable.

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

None.