| Value | Category | Cases | |
|---|---|---|---|
| 1 | No | 30 |
1.5%
|
| 2 | Once | 1 |
0.1%
|
| 3 | More than once | 0 |
0%
|
| 4 | Not applicable | 1954 |
98.3%
|
| Sysmiss | 3 |