| Value | Category | Cases | |
|---|---|---|---|
| 1 | Within past month | 2264 |
69.7%
|
| 2 | Within past 3 months | 549 |
16.9%
|
| 3 | Within 6 months | 158 |
4.9%
|
| 4 | More than 6 months ago | 277 |
8.5%
|
| Sysmiss | 9232 |