One of the characteristics which differentiates the ESEE of other statistics sources about firms is its explicit goal of generating information with a panel structure. On the one hand, since the firms are complex entities which can be subjected to changes which modify their legal nature, it has been necessary to keep a systematic record of these changes. The ESEE collects a wide range of decisions which imply extraordinary transformations in the life of the firms, and which must be controlled for making sure its yearly data can be compared: mergers, acquisitions, spin-offs, redundancies, spin-off of workforces or of tangible fixed assets, etc.

On the other hand, the above has made it necessary a specific effort for refining and validating the information provided by the firms in order to guarantee its quality and consistency through time. All the information included into the ESEE is subjected to validation and logical consistency controls, and in no case values are assigned when there is no answer from the company. For further information about criteria for validation content of the ESEE, please link here .