| Value | Category | Cases | |
|---|---|---|---|
| -999 | -999 | 5 |
1.4%
|
| -888 | -888 | 109 |
30.4%
|
| 1 | More than one month | 26 |
7.2%
|
| 2 | Once every month | 17 |
4.7%
|
| 3 | Once every two months | 22 |
6.1%
|
| 4 | Once every three months | 92 |
25.6%
|
| 5 | Less than once every three months | 88 |
24.5%
|
| Sysmiss | 553 |