This seems pretty simple but I can't find how to do it.
I keep a Google Sheet where I add several times a day new lines as following :
| A | B | C |
| --- | --- | --- |
1 | John | 10 | 50 |
2 | Peter | 20 | 70 |
3 | John | 14 | |
4 | Peter | 12 | 82 |
5 | John | 5 | 55 |
I'm trying to get the average rating of the last N lines for a given name. That way I can send a report to "name" every now and then with an average of his N last ratings.