class | Degree of reliability | Tilt directions | Degree |
A | Very good | South, Southeast and Southwest | 5.112 - 5.247 |
B | Average | Eastern | 5.67 - 5.112 |
C | Weak | Western | 5.247 - 5.292 |
D | Inappropriate | North, Northeast and Northwest | 5.292 - 5.22 |