| Value | Category | Cases | |
|---|---|---|---|
| 1 | Months | 234 |
11.9%
|
| 2 | Years | 1151 |
58.6%
|
| 3 | Always | 573 |
29.2%
|
| 4 | Other | 6 |
0.3%
|
| 99 | N/A | 0 |
0%
|
| Sysmiss | 33 |