| Term | Coefficient | T | P |
| Constant | −166.22 | −12.37 | 0.000 |
| X1 | 0.56 | 16.12 | 0.000 |
| X2 | 32.90 | 13.31 | 0.000 |
| X3 | 0.65 | 8.82 | 0.000 |
| X12 | 0 | −15.11 | 0.000 |
| X22 | 0.35 | 1.39 | 0.222 |
| X32 | −0.001 | −4.16 | 0.009 |
| X1X2 | −0.032 | −12.93 | 0.000 |
| X1X3 | 0 | 0.064 | 0.952 |
| X2X3 | −0.181 | −22.31 | 0.000 |