In 2021, the SLFS was changed from a survey conducted only by telephone to a multimode survey (internet and telephone survey) with the emphasis on the internet survey. In addition, the 2021 questionnaire was slightly modified to comply with the new Eurostat requirements, which also came into force in January 2021.
The changes in the questionnaire, the switch to the multi-mode survey and the new base for calculating underemployment (usual instead of normal hours worked) result in a break in the time series.
The new figures on underemployment are only published for the second quarter of 2022 onwards, as the transition to the multimode survey is only fully completed in this quarter. Data from 2004 to 2020 were not compiled on the same base and are not comparable with 2022.