| Value | Category | Cases | |
|---|---|---|---|
| -999 | -999 | 1 |
0.9%
|
| -888 | -888 | 14 |
12.1%
|
| 1 | More than one month | 8 |
6.9%
|
| 2 | Once every month | 9 |
7.8%
|
| 3 | Once every two months | 7 |
6%
|
| 4 | Once every three months | 37 |
31.9%
|
| 5 | Less than once every three months | 40 |
34.5%
|
| Sysmiss | 796 |