CIGRE working group A2.62 (Analysis of AC transformer reliability) with Prof. Tenbohlen as convenor started to collect and analyse worldwide failure data of power transformers by means of a standardized survey. We are looking for major failures and retirements in the time period between 2010 and 2019. The questionnaire is optimized based on the first experience and was approved by CIGRE Central Office. The confidentiality is given, because it will not be possible to deduce statistics of an individual utility from the publications of the working group. The questionnaire can be downloaded here: