| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 5.9 | 7.6 | ||||||||||
| 2 | 4.2 | 7.1 | ||||||||||
| 3 | 3.0 | 2.7 | ||||||||||
| 4 | 2.7 | 7.2 | ||||||||||
| 5 | 2.3 | 4.6 | ||||||||||
| 6 | 3.8 | 6.4 | ||||||||||
| 7 | 6.2 | 9.3 | ||||||||||
| 8 | 2.9 | 10.2 | ||||||||||
| 9 | 3.8 | 10.4 | ||||||||||
| 10 | 4.2 | 8.0 | ||||||||||
| 11 | 9.9 | 11.1 | ||||||||||
| 12 | 10.4 | 6.1 | ||||||||||
| 13 | 8.8 | 4.1 | ||||||||||
| 14 | 6.4 | 7.1 | ||||||||||
| 15 | 7.1 | 6.2 | ||||||||||
| 16 | 6.6 | 7.0 | ||||||||||
| 17 | 8.3 | 5.3 | ||||||||||
| 18 | 6.7 | 5.2 | ||||||||||
| 19 | 8.9 | 5.7 | ||||||||||
| 20 | 9.7 | 10.4 | ||||||||||
| 21 | 8.9 | 14.6 | ||||||||||
| 22 | 7.4 | |||||||||||
| 23 | 7.2 | |||||||||||
| 24 | 8.0 | |||||||||||
| 25 | 5.8 | |||||||||||
| 26 | 5.3 | |||||||||||
| 27 | 6.7 | |||||||||||
| 28 | 8.6 | |||||||||||
| 29 | 4.2 | |||||||||||
| 30 | 7.2 | |||||||||||
| 31 | 10.0 | |||||||||||
| Avg: | 6.5 | * 7.4 | ||||||||||
| Hi: | 10.4 | * 14.6 | ||||||||||
| Lo: | 2.3 | * 2.7 | ||||||||||
| Note: | *Incomplete dataset. | |||||||||||
| Avg | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | 6.5 | * 7.4 | ||||||||||
| 2025 | 6.0 | 8.3 | 13.8 | 17.3 | 19.4 | 23.9 | 24.1 | 23.4 | 19.0 | 14.7 | 11.1 | 9.2 |
| 2024 | 7.7 | 11.1 | 12.0 | 13.9 | 19.5 | 20.2 | 22.3 | 22.8 | 18.2 | 15.0 | 10.1 | 9.5 |
| 2023 | 8.6 | 10.4 | 10.9 | 13.6 | 18.4 | 23.3 | 21.1 | 22.0 | 22.1 | 16.0 | 10.3 | 9.0 |
| 2022 | 8.2 | 10.7 | 13.0 | 14.9 | 19.1 | 21.7 | 25.5 | 25.5 | 19.7 | 16.9 | 11.6 | 6.8 |
| 2021 | 5.6 | 8.8 | 12.0 | 12.9 | 16.1 | 21.6 | 24.1 | 21.2 | 21.7 | 16.1 | 11.2 | 8.6 |
| 2020 | 9.4 | 9.9 | 11.1 | 16.5 | 19.4 | 20.0 | 20.6 | 22.2 | 19.2 | 13.6 | 11.5 | 7.4 |
| 2019 | 7.0 | 11.5 | 12.2 | 14.8 | 16.9 | 19.1 | 23.1 | 22.7 | 19.0 | 13.2 | 8.4 | 8.2 |
| 2018 | 7.8 | 6.0 | 8.5 | 13.7 | 19.2 | 21.4 | 25.4 | 22.4 | 18.8 | 15.2 | 10.8 | 9.2 |
| 2017 | 6.6 | 8.8 | 12.9 | 14.3 | 18.1 | 20.9 | 21.7 | 20.8 | 18.0 | 15.7 | 10.0 | 7.6 |
| 2016 | 8.2 | 8.5 | 9.7 | 12.4 | 17.3 | 19.4 | 22.2 | 22.4 | 20.5 | 14.4 | 8.8 | 8.8 |
| 2015 | 7.9 | 7.3 | 10.7 | 15.1 | 15.6 | 19.8 | 21.5 | 21.5 | 17.6 | 14.7 | 12.0 | 12.1 |
| 2014 | 8.4 | 9.4 | 12.6 | 15.1 | 17.2 | 20.4 | 23.8 | 20.1 | 19.7 | 15.6 | 10.8 | 8.1 |
| 2013 | 5.6 | 5.9 | 5.3 | 12.6 | 16.1 | 19.1 | 24.5 | 22.4 | 18.5 | 15.6 | 9.5 | 9.5 |
| 2012 | 8.3 | 7.7 | 13.8 | 11.7 | 17.0 | 17.9 | 20.4 | 21.9 | 18.1 | 12.9 | 9.5 | 7.4 |
| 2011 | 6.8 | 9.3 | 11.7 | 18.2 | 17.8 | 20.2 | 21.2 | 21.1 | 20.7 | 16.9 | 12.0 | 8.6 |
| 2010 | 3.9 | 5.3 | 10.8 | 14.8 | 16.5 | 21.4 | 22.3 | 20.3 | 18.6 | 14.0 | 7.9 | 2.4 |
| 2009 | 6.0 | 7.5 | 11.9 | 15.5 | 17.4 | 20.7 | 21.5 | 22.1 | 19.2 | 15.3 | 11.5 | 5.6 |
| 2008 | 9.6 | 9.6 | 10.4 | 12.7 | 18.6 | 19.5 | 22.0 | 21.6 | 18.1 | 14.0 | 9.9 | 6.7 |
| 2007 | 9.9 | 9.4 | 11.5 | 17.2 | 16.5 | 20.0 | 20.0 | 21.6 | 19.0 | 15.3 | 10.8 | 7.6 |
| 2006 | 6.9 | 6.9 | 8.4 | 13.1 | 17.3 | 22.3 | 26.9 | 21.0 | 21.9 | 16.4 | 11.8 | 9.2 |
| 2005 | 9.1 | 7.2 | 10.7 | 14.1 | 16.9 | 21.0 | 21.8 | 22.0 | 20.0 | 16.2 | 9.7 | 7.6 |
| 2004 | 8.1 | 8.6 | 10.7 | 14.6 | 18.0 | 20.7 | 21.0 | 22.6 | 19.2 | 13.9 | 10.7 | 8.5 |
| 2003 | 7.3 | 7.6 | 13.1 | 15.2 | 17.5 | 22.1 | 23.0 | 24.0 | 20.4 | 13.4 | 11.0 | 7.4 |
| 2002 | 8.4 | 10.5 | 11.8 | 14.8 | 16.9 | 19.8 | 21.4 | 22.7 | 19.1 | 13.3 | 10.7 | 7.1 |
| 2001 | 5.8 | 8.4 | 8.5 | 12.0 | 18.4 | 19.4 | 22.2 | 22.4 | 17.1 | 16.6 | 10.9 | 6.8 |
| 2000 | 22.2 | 19.0 | 13.8 | 9.6 | 7.7 | |||||||
| Avg | 7.4 | * 8.5 | 11.1 | 14.4 | 17.6 | 20.6 | 22.6 | 22.1 | 19.3 | 14.9 | 10.5 | 8.0 |