Hello Everyone!!
I need to obtain weekly means for some measurements. I need a weekly mean by subject and week for each of them. I'm not able to do it


+----------------------------------------+
| CODICE Settim~a GLI1 GLI2 |
|----------------------------------------|
1. | 20008 1 101 98 |
2. | 20008 2 95 100 |
3. | 20008 3 102 113 |
4. | 20008 3 110 90 |
5. | 20008 3 113 91 |
|----------------------------------------|
6. | 20008 3 113 91 |
7. | 20008 4 101 . 104 |
8. | 20008 5 92 91 |
9. | 20008 5 104 101 |
10. | 20008 6 101 85 |
+----------------------------------------+

Where CODICE stands for id, Settimana stands for a week, and GLI1, GLI2, and GLI3 are the measurements
Thank you all in advance