| Value | Category | Cases | |
|---|---|---|---|
| 1 | Very common | 20 |
0.9%
|
| 2 | Fairly common | 25 |
1.1%
|
| 3 | Fairly rare | 164 |
7.5%
|
| 4 | Very rare | 1720 |
78.3%
|
| 9 | Don't know | 269 |
12.2%
|