| Months | Cu | S. Dev | SDS | Months | Pb | S. Dev | SDS | Months | Zn | S. Dev | SDS |
| September | 0.47 | 0.02 | 0.1 | September | 0.52 | 0.02 | 0.2 | September | 0.99 | 0.01 | 5 |
| October | 0.44 | 0.02 | 0.1 | October | 0.53 | 0.02 | 0.2 | October | 0.97 | 0.02 | 5 |
| November | 0.49 | 0.02 | 0.1 | November | 0.54 | 0.02 | 0.2 | November | 1.07 | 0.12 | 5 |
| December | 0.49 | 0.03 | 0.1 | December | 0.58 | 0.01 | 0.2 | December | 1.58 | 0.03 | 5 |
| January | 0.39 | 0.02 | 0.1 | January | 0.62 | 0.02 | 0.2 | January | 0.76 | 0.55 | 5 |
| February | 0.34 | 0.03 | 0.1 | February | 0.32 | 0.02 | 0.2 | February | 1.90 | 0.02 | 5 |
| March | 0.64 | 0.03 | 0.1 | March | 0.72 | 0.01 | 0.2 | March | 1.97 | 0.02 | 5 |
| April | 0.42 | 0.02 | 0.1 | April | 0.63 | 0.03 | 0.2 | April | 1.85 | 0.04 | 5 |