Hi @berwickgeek ,
Take a look at this cloneable app,
There are some bugs or preventions that need to be placed and solved, but the whole operation bring the expected result.
Let me know if it does not suit you, but better after revising the ranking collection with your data.
To start, click clear competitor’s pickup and to begin iteration, click pickup competitor and to do another iteration click again.
This is to show the basic operation and still need a lot of adjustment/revision to make it smooth and reflect your database layout.
Hope you find this as a start.