| Value | Category | Cases | |
|---|---|---|---|
| 1 | Voluntary | 4132 |
28.8%
|
| 2 | Compulsory | 6891 |
48%
|
| 7 | N/A | 1846 |
12.9%
|
| 8 | Invalid | 94 |
0.7%
|
| 9 | Missing | 1402 |
9.8%
|