| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 215 |
68.5%
|
| 1 | One hour or less | 0 |
0%
|
| 6 | 4 |
1.3%
|
|
| 7 | 2 |
0.6%
|
|
| 8 | 2 |
0.6%
|
|
| 9 | 1 |
0.3%
|
|
| 10 | 4 |
1.3%
|
|
| 12 | 30 |
9.6%
|
|
| 14 | 1 |
0.3%
|
|
| 16 | 14 |
4.5%
|
|
| 20 | 4 |
1.3%
|
|
| 24 | 12 |
3.8%
|
|
| 28 | 1 |
0.3%
|
|
| 35 | 1 |
0.3%
|
|
| 36 | 5 |
1.6%
|
|
| 40 | 3 |
1%
|
|
| 48 | 2 |
0.6%
|
|
| 60 | 4 |
1.3%
|
|
| 64 | 1 |
0.3%
|
|
| 72 | 1 |
0.3%
|
|
| 80 | 1 |
0.3%
|
|
| 100 | 1 |
0.3%
|
|
| 120 | 1 |
0.3%
|
|
| 200 | 1 |
0.3%
|
|
| 480 | 1 |
0.3%
|
|
| 500 | 1 |
0.3%
|
|
| 504 | 1 |
0.3%
|
|
| Sysmiss | 284 |