When using a calculation method on a trend log list or trend chart with the period "Month" the timestamp is always on the 16th of each month.
See the example below:
Why is the time stamp always the 16th and is it possible to change the collection date
EcoStruxure Building Operation
Building Operation Workstation
When doing a calculation in a trend log list or trend chart the timestamp will always be in the middle of the chosen period.
This is currently not possible to change in EBO.
Alternative ways of presenting the data are to use Dashboards or Notification reports