| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 |
1.5%
|
| -7 | Does not apply is a floor in a building (spontaneous) | 7 |
1.7%
|
| 0 | 383 |
93.6%
|
|
| 1 | 2 |
0.5%
|
|
| 15 | 1 |
0.2%
|
|
| 30 | 1 |
0.2%
|
|
| 50 | 1 |
0.2%
|
|
| 80 | 1 |
0.2%
|
|
| 100 | 7 |
1.7%
|