Hi
So you have a field containing WaitingTime and want to transform this into average waiting time?
You also have a field containing month values that you want to use as a dimension?
If this is the case then create a line chart select Month as a dimension and use the expression avg(WaitingTime).
I guess it might not be quite so simple, in that case please clarify and and an example of the data you need to transform.
Regards
