| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 17 |
2.2%
|
| -7 | Does not apply is a floor in a building (spontaneous) | 195 |
25.7%
|
| 0 | 147 |
19.3%
|
|
| 50 | 14 |
1.8%
|
|
| 60 | 5 |
0.7%
|
|
| 70 | 10 |
1.3%
|
|
| 80 | 8 |
1.1%
|
|
| 90 | 4 |
0.5%
|
|
| 100 | 360 |
47.4%
|