First off I am sorry if there is an example already in the community which I have missed. I have spent time looking for answers and I have not had any luck... but then again I suspect I am missing something.
I have been asked to produced the following chart:
and I am trying to create the Client column on the far left... and I am not having any luck with getting the grouping working.
Would anybody be able to provide me a simple example or link that I could work from to create the table?