| Variables | Yellowing index | Brown index | Clarity | Turbidity (NTU) |
| Yellowing index | 1 |
|
|
|
| Brown index | 0.97 | 1 |
|
|
| Clarity | −0.99 | −0.97 | 1 |
|
| Turbidity (NTU) | 0.45 | 0.53 | −0.39 | 1 |