| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 22.8 | 22.4 | ||||||||||
| 2 | 21.9 | 18.9 | ||||||||||
| 3 | 23.3 | 25.0 | ||||||||||
| 4 | 22.7 | 23.4 | ||||||||||
| 5 | 24.2 | 23.3 | ||||||||||
| 6 | 22.7 | 21.2 | ||||||||||
| 7 | 22.4 | 21.9 | ||||||||||
| 8 | 25.1 | 25.4 | ||||||||||
| 9 | 22.8 | 22.6 | ||||||||||
| 10 | 21.4 | 26.3 | ||||||||||
| 11 | 22.9 | 26.3 | ||||||||||
| 12 | 21.9 | |||||||||||
| 13 | 23.9 | |||||||||||
| 14 | 23.9 | |||||||||||
| 15 | 20.4 | |||||||||||
| 16 | 23.3 | |||||||||||
| 17 | 25.2 | |||||||||||
| 18 | 23.6 | |||||||||||
| 19 | 24.3 | |||||||||||
| 20 | 21.9 | |||||||||||
| 21 | 22.5 | |||||||||||
| 22 | 22.2 | |||||||||||
| 23 | 21.5 | |||||||||||
| 24 | 19.6 | |||||||||||
| 25 | 19.6 | |||||||||||
| 26 | 21.1 | |||||||||||
| 27 | 22.6 | |||||||||||
| 28 | 26.1 | |||||||||||
| 29 | 21.4 | |||||||||||
| 30 | 24.8 | |||||||||||
| 31 | 22.3 | |||||||||||
| Avg: | 22.7 | * 23.3 | ||||||||||
| Hi: | 26.1 | * 26.3 | ||||||||||
| Lo: | 19.6 | * 18.9 | ||||||||||
| Note: | *Incomplete dataset. | |||||||||||
| Avg | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | 22.7 | * 23.3 | ||||||||||
| 2025 | 23.2 | 25.1 | 22.8 | 22.0 | * 17.6 | 15.7 | 14.6 | 15.2 | 16.0 | 17.2 | 21.4 | 22.0 |
| 2024 | 24.7 | 23.1 | 20.9 | 20.0 | 16.6 | 16.1 | 15.2 | 15.2 | 15.8 | 18.2 | 19.4 | 22.4 |
| 2023 | 25.1 | 23.7 | 21.4 | 20.7 | 18.9 | 16.5 | 14.9 | 13.8 | 16.8 | 17.1 | 19.4 | 21.9 |
| 2022 | 24.5 | 24.3 | 23.2 | 20.5 | 18.1 | 15.5 | 14.7 | 15.5 | 16.4 | 17.2 | 20.6 | * 23.3 |
| 2021 | 21.1 | * 21.3 | 20.8 | 18.8 | 16.4 | 15.4 | 13.9 | 14.1 | 14.8 | 16.7 | 19.2 | 21.6 |
| 2020 | 20.3 | 21.8 | 19.5 | 18.0 | 16.7 | 15.2 | 13.6 | 14.8 | 14.6 | 16.7 | 18.6 | 19.1 |
| 2019 | 21.9 | 21.3 | * 21.3 | 16.8 | 16.8 | 13.5 | 12.7 | * 12.7 | 14.2 | * 15.0 | 17.7 | 19.9 |
| 2018 | 0.0 | 9.5 | 21.0 | 18.1 | 14.5 | * 13.9 | * 12.8 | 14.0 | 14.3 | 15.8 | 18.2 | 21.0 |
| 2017 | 18.3 | 4.3 | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.0 | * 0.0 | 0.0 | 0.0 | 0.0 |
| 2016 | 22.4 | 23.8 | 21.1 | 19.1 | 16.7 | 14.7 | * 13.6 | 12.6 | 14.7 | 15.6 | 16.4 | 18.6 |
| 2015 | 22.6 | 20.5 | 20.8 | 18.2 | 15.4 | 13.7 | 12.1 | 12.8 | 13.5 | 15.2 | * 16.4 | 18.4 |
| 2014 | * 19.5 | 21.1 | 19.2 | 18.7 | 15.6 | 14.6 | 12.6 | 13.0 | 14.8 | 15.2 | 15.8 | 19.0 |
| 2013 | 21.4 | 21.5 | 21.0 | * 18.5 | * 15.5 | 13.6 | 13.1 | 14.7 | 14.6 | 15.3 | 19.6 | 22.8 |
| 2012 | 21.1 | 21.2 | 19.0 | 18.9 | 14.8 | 12.8 | 12.9 | 14.2 | 14.7 | 15.3 | * 16.1 | 20.4 |
| 2011 | 21.6 | * 21.6 | 20.2 | 16.9 | 17.2 | 14.3 | 12.6 | 12.1 | 13.7 | 16.1 | 16.7 | 20.1 |
| 2010 | 23.8 | 26.1 | * 23.8 | 21.1 | 19.6 | * 14.9 | * 14.8 | * 14.0 | 15.5 | 17.9 | 20.6 | |
| 2009 | * 26.1 | 24.7 | 23.3 | 21.6 | 16.6 | 15.4 | 15.3 | 17.8 | 17.7 | 16.9 | 19.2 | 21.8 |
| 2008 | 22.3 | 23.4 | ||||||||||
| Avg | * 21.1 | * 21.0 | * 20.0 | * 18.1 | * 15.7 | * 13.8 | * 12.9 | * 13.4 | * 14.2 | * 15.2 | * 17.5 | * 19.8 |