The trace in question has aggregation set to No, as in this sample from the ABAP Trace Requests view.
If a trace is aggregated, then the trace does not record individual trace events. The Call Sequence function is not offered in the context menu if a trace was recorded with aggregation active.
Use the Call Sequence view to analyze the execution path of a program. You can use the Call Sequence to do the following, for example:
Here is how to use the Call Sequence to analyze the flow of program execution.
We now understand basically how the class works and what runtime resources it consumes.