| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 25 |
9.2%
|
| -7 | Does not apply is a floor in a building (spontaneous) | 8 |
3%
|
| 0 | 35 |
12.9%
|
|
| 5 | 2 |
0.7%
|
|
| 25 | 1 |
0.4%
|
|
| 50 | 4 |
1.5%
|
|
| 70 | 3 |
1.1%
|
|
| 80 | 2 |
0.7%
|
|
| 100 | 191 |
70.5%
|