| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1. dark gloomy | 204 |
4.7%
|
| 2 | 2. poor light | 616 |
14.1%
|
| 3 | 3. average light | 1913 |
43.9%
|
| 4 | 4. bright | 1521 |
34.9%
|
| 77 | 77. d/r | 0 |
0%
|
| 99 | 99. missing | 107 |
2.5%
|
| Sysmiss | 177 |