| Value | Category | Cases | |
|---|---|---|---|
| 0 | Not one of the three most important sources | 90 |
92.8%
|
| 1 | First rank | 1 |
1%
|
| 2 | Second rank | 0 |
0%
|
| 3 | Third rank | 5 |
5.2%
|
| 4 | 1 |
1%
|
|
| -9 | 5 | ||
| -7 | 31 |