| Value | Category | Cases | |
|---|---|---|---|
| 1 | less than a month | 73 |
20%
|
| 2 | 1-2 months | 128 |
35.1%
|
| 3 | 2-3 months | 70 |
19.2%
|
| 4 | more than 3 months | 94 |
25.8%
|
| Sysmiss | 4279 |