Correlation coefficients of the cross correlation function between air pollution and temporal variables using Spearman rank correlation
| Day of the week | Year | Season | NO | PM10 | O3 | |
| Day of the week | 0.003 | 0.000 | 0.040 | 0.099 | −0.024 | |
| Year | 0.930 | 0.066 | 0.038 | −0.067 | 0.056 | |
| Season | 0.990 | 0.027 | 0.124 | 0.009 | 0.005 | |
| NO | 0.187 | 0.199 | <0.001 | 0.278 | −0.646 | |
| PM10 | 0.001 | 0.028 | 0.777 | <0.001 | −0.203 | |
| O3 | 0.419 | 0.063 | 0.868 | <0.001 | <0.001 |
Note: above the diagonal are the correlation coefficients r, below all p values
NO, nitric oxide; O3, ozone; PM10, particulate matter with an aerodynamic diameter of ≤10 µm.