Why do financial figures of two different years sometimes have the same annual financial statement as a source?

Example: The key figures for 2019 and 2018 are sourced from the "Annual Financial Statement 2019". This article explains why this happens.

The annual financial statements published by the Federal Gazette always include the figures of the current and previous annual financial statements. For example, the annual financial statement for 2018 contains data for both 2018 and 2017.

In this case, there are two sources for the annual financial statement 2017 and often with different data. The decision as to which data will be displayed is made on a case by case basis, which is determined assessing various quality criteria. In most cases the more recent data "overwrites" older data from annual financial statements, which often contain more information than the previous one.