| Value | Category | Cases | |
|---|---|---|---|
| 1 | AC | 21 |
14.4%
|
| 2 | DC | 34 |
23.3%
|
| 3 | Portable | 21 |
14.4%
|
| 888 | Don?t know | 70 |
47.9%
|
| Sysmiss | 135 |