| Value | Category | Cases | |
|---|---|---|---|
| 1 | Through tube | 39767 |
14.7%
|
| 2 | Special hollow | 140044 |
51.7%
|
| 3 | Outside of house | 63633 |
23.5%
|
| 4 | No special place | 27259 |
10.1%
|
| Sysmiss | 275440 |