0%, |
 
25 (28.7%)
|
1-2%, |
 
16 (18.4%)
|
3-4%, |
 
18 (20.7%)
|
5-6%, |
 
11 (12.6%)
|
7-8%, |
 
2 (2.3%)
|
9-10%, |
 
2 (2.3%)
|
大于10% |
 
13 (14.9%)
|