The following works for me:
bysort packageid: generate n = _n
bysort packageid: egen cov_sum = max(n)
list, abbreviate(15)
+----------------------------------------+
| packageid CovenantType n cov_sum |
|----------------------------------------|
1. | 4106 13 1 2 |
2. | 4106 18 2 2 |
3. | 4812 13 1 1 |
4. | 4952 2 1 1 |
5. | 5223 9 1 1 |
|----------------------------------------|
6. | 5287 18 1 1 |
7. | 7011 4 1 3 |
8. | 7011 13 2 3 |
9. | 7011 18 3 3 |
10. | 7849 17 1 1 |
|----------------------------------------|
11. | 10261 17 1 1 |
12. | 11057 4 1 1 |
13. | 11178 4 1 3 |
14. | 11178 13 2 3 |
15. | 11178 18 3 3 |
|----------------------------------------|
16. | 11452 17 1 1 |
17. | 11714 4 1 2 |
18. | 11714 13 2 2 |
19. | 11954 2 1 3 |
20. | 11954 13 2 3 |
|----------------------------------------|
21. | 11954 18 3 3 |
22. | 12807 13 1 2 |
23. | 12807 18 2 2 |
+----------------------------------------+
bysort packageid : gen cov_sum = _Nwould seem to be more direct. (You know this really....)@NickCox, I wanted to show to the OP the steps.