CSO publication, 07 March 2024, 11am

Information Note – Census Revision to SILC 2020 - SILC 2022

The annual Survey of Income and Living Condition (SILC) is a sample survey and requires independent estimates of population and the numbers of private households each year to ensure the survey results are reflective of the population as a whole. For example, household composition distribution benchmarks are used as part of the SILC weighting procedure and when results from a new Census of Population become available, SILC outputs in the period between censuses (intercensal period) are analysed to determine if revisions to these outputs are necessary.

Results from the Census of Population 2022 provide the most timely and accurate population estimates available for the intercensal period 2017 to 2022. Estimates in today’s SILC publications (07 March 2024) and PxStat (CSO’s data dissemination database) now reflect the revised SILC 2020, 2021, and 2022 statistics based upon the updated population benchmarks from Census 2022.

The revisions to population benchmarks impacted the overall SILC results by increasing the estimate of median household disposable income and equivalised disposable income while decreasing estimated poverty rates. Intercensal household composition benchmarks over-estimated the proportion of households composed of a single adult. Household income is highly correlated with household size and as a consequence, published average household income values in SILC 2020, 2021, and 2022 were lower than the revised values. To address this for future iterations of SILC, the CSO has changed its method of calculating benchmark estimates in the intercensal period.  

Article 4.1. of Commission Implementing Regulation (EU) 2019/2242, states that ‘The target population in the income and living conditions domain shall be private households and all persons composing these households in the territory of the Member State’. In other words, statistics published from the SILC survey should relate to persons usually resident in private households. As part of the process of revising population estimates for SILC 2020 to 2022, Census of Population 2022 data and administrative data from other sources (e.g. number of Ukrainians living in communal establishments and number of International Protection Accommodation Services (IPAS) applicants) were used. This enabled the production of revised population estimates that exclude people living in communal establishments. For further information on benchmark totals used in the SILC weighting procedures for survey years 2020-2022 and changes to method used for benchmark estimation in the intercensal period, see Background notes and Frequently Asked Questions.

For more detail on impact of these revisions, Table 1a below compares published and revised SILC income and poverty statistics and Table 1b compares published and revised SILC enforced deprivation statistics.

The CSO constantly seeks to improve the accuracy of its surveys by benchmarking them against the most up-to-date information available. This is in line with standard procedures for reviewing and updating statistical releases. Where updates are made, users are informed at the point of change and a full list of changes is provided.