IST Small Area Socioeconomic Index

The Small Area Socioeconomic Index is a synthetic index by small areas that summarises various socioeconomic characteristics of the population into a single value. The Index brings together information on the employment situation, educational attainment [MHM1.1]level, immigration status and income of all persons residing in each territorial unit, based on 6 sectoral indicators.

The Small Area Socioeconomic Index is a relative index, without units of measurement. It establishes a reference value for Catalonia equal to 100 and a value for each territorial unit in comparison with the average value for Catalonia.

The results are presented by census tract group, a division of Catalonia into territorial units with an average of 9,000 people. Each census tract group is made up of a set of territorially contiguous census tracts with similar socioeconomic characteristics. Out of the 853 census tract groups currently established for Catalonia, 713 are inframunicipal, 26 correspond to one municipality each and 114 are supramunicipal (groups of municipalities within their county). Results are also provided by census tract, municipality, neighbourhoods of Barcelona , counties and for Catalonia as a whole.

The Small Area Socioeconomic Index is published annually and contains data from 2015 onwards.

The data are disseminated annually in two phases: the provisional data and the definitive data. Regarding the provisional data, out of the 6 indicators of the Small Area Socioeconomic Index, 5 correspond to data from the reference year, while the income indicator corresponds to data from the year prior to the reference year. Regarding the definitive data, all 6 indicators correspond to data from the reference year. The provisional results remain valid until they are replaced, each year, by the definitive IST, which is calculated once the income for the reference year is available.