| Value | Category | Cases | |
|---|---|---|---|
| 1 | MANDATORY | 3562 |
44.6%
|
| 2 | VOLUNTARY | 324 |
4.1%
|
| 3 | BOTH | 71 |
0.9%
|
| 4 | DON'T KNOW | 854 |
10.7%
|
| 5 | NONE | 3184 |
39.8%
|