| Value | Category |
|---|---|
| -5 | other |
| -4 | missing data |
| -3 | refused to answer |
| -2 | not applicable |
| -1 | do not know |
| 0 | |
| 20 | |
| 50 | |
| 120 | |
| 130 | |
| 140 | |
| 150 | |
| 200 | |
| 240 | |
| 300 | |
| 360 | |
| 400 | |
| 475 | |
| 500 | |
| 520 | |
| 600 | |
| 700 | |
| 800 | |
| 900 | |
| 1000 | |
| 1200 | |
| 1400 | |
| 1500 | |
| 1600 | |
| 1750 | |
| 1800 | |
| 2000 | |
| 2200 | |
| 2400 | |
| 2600 | |
| 3000 | |
| 3300 | |
| 3360 | |
| 3600 | |
| 4200 | |
| 4560 | |
| 4800 | |
| 5000 | |
| 6000 | |
| 7200 | |
| 9000 | |
| 10000 | |
| 10800 | |
| 11000 | |
| 12000 |