| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 |
0.3%
|
| -7 | Does not apply is a floor in a building (spontaneous) | 51 |
14.2%
|
| 0 | 298 |
82.8%
|
|
| 20 | 1 |
0.3%
|
|
| 90 | 1 |
0.3%
|
|
| 100 | 8 |
2.2%
|