| Variables | Y | X1 | X2 | X3 | X4 |
| Y | 1.000 |
|
|
|
|
| X1 | 0.970*** | 1.000 |
|
|
|
| X2 | 0.975*** | 0.999*** | 1.000 |
|
|
| X3 | −0.518** | −0.614*** | −0.609*** | 1.000 |
|
| X4 | 0.992*** | 0.987*** | 0.989*** | −0.582** | 1.000 |