ESS guidelines on seasonal adjustment : 2024 edition

The establishment of common guidelines for seasonal adjustment within the European Statistical System is an essential step towards a better harmonisation and comparability of infra-annual statistics. Following the 2009 and 2015 editions which were widely accepted and implemented, the 2024 revised ESS Guidelines on Seasonal Adjustment present theoretical aspects and practical implementation issues in a user friendly and easy to read framework, thereby addressing both experts and non-experts in seasonal adjustment. The ESS Guidelines on Seasonal Adjustment foster the transparency of seasonal adjustment practices by encouraging the documentation of all seasonal adjustment steps and the dissemination of metadata on seasonal adjustment and foster the development of expertise and capacity building. The revised guidelines include a new section on the seasonal adjustment of high frequency data and new items on the treatment of shocks and the handling of long time series, describe better the different steps in seasonal adjustment, and specify in more detail alternative practices.