| Site | Absolute low CER1 | Date | Absolute high CER | Date | Ratio high:low |
|---|---|---|---|---|---|
| Wall - Battery | 5.6±0.22 | Aug 1 | 16.6±0.6 | Dec 19 | 3.0 |
| Fourth Avenue | 4.6±0.2 | Aug 1 | 11.6±0.4 | Feb 17 | 2.5 |
| Ranier Tower | 4.4±0.2 | Aug 1 | 11.2±0.3 | Feb 17 | 2.5 |
| Seneca Street | 4.5±0.1 | Aug 1 | H.0±0.3 | Apr 25 | 2.4 |
| Freeway Park | 4.4±0.2 | Aug 1 | 11.5±0.6 | Dec 19 | 2.6 |
| East John | 2.1+0.3 | Aug 1 | 12.1±0.7 | Dec 19 | 5.8 |
| All sites | 4.2±0.4 | Aug 1 | 12.9±0.9 | — | 3.1 |