autoformat by condition "number of (completed) tasks"

[TMZ]

I want to use MLO to count the times I do sports in a week.

So I create one folder for every week and create a task for every sports activity I'm planning to do next week and when I did that activity, I  mark the task as completed.

Is there a way to count the number of completed tasks in a folder?

It would be great, if weeks (=folders) with more than 5 times, I did sport could be marked in colour or with a symbol (golden goblet? :D)