| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 21 |
1.3%
|
| -7 | Does not apply is a floor in a building (spontaneous) | 407 |
24.5%
|
| 0 | 363 |
21.8%
|
|
| 10 | 1 |
0.1%
|
|
| 20 | 1 |
0.1%
|
|
| 25 | 1 |
0.1%
|
|
| 30 | 4 |
0.2%
|
|
| 40 | 1 |
0.1%
|
|
| 50 | 34 |
2%
|
|
| 60 | 8 |
0.5%
|
|
| 70 | 10 |
0.6%
|
|
| 75 | 2 |
0.1%
|
|
| 80 | 11 |
0.7%
|
|
| 85 | 2 |
0.1%
|
|
| 100 | 797 |
47.9%
|