| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 |
0%
|
| 1 | Cubic meters | 168 |
36.5%
|
| 2 | Gallons | 288 |
62.6%
|
| 3 | Cubic feet | 4 |
0.9%
|
| 4 | Other | 0 |
0%
|
| Sysmiss | 253 |