| Value | Category | Cases | |
|---|---|---|---|
| 1 | Last month | 29 |
15.3%
|
| 2 | 1-6 months ago | 73 |
38.4%
|
| 3 | 6-12 months ago | 42 |
22.1%
|
| 4 | More than a year ago | 46 |
24.2%
|
| 9 | Missing | 0 |
0%
|
| Sysmiss | 627 |