| Jan | Feb | March | April | May | June | July | Aug | Sept | Oct | Nov | Dec |
|---|
| 1 | 14.7 | 18.8 | 17.4 | | | | | | | | | |
|---|
| 2 | 16.1 | 22.7 | 18.4 | | | | | | | | | |
|---|
| 3 | 17.2 | 22.0 | 20.3 | | | | | | | | | |
|---|
| 4 | 16.7 | 21.8 | 20.0 | | | | | | | | | |
|---|
| 5 | 18.2 | 22.3 | 18.1 | | | | | | | | | |
|---|
| 6 | 19.6 | 20.6 | 15.1 | | | | | | | | | |
|---|
| 7 | 19.2 | 18.9 | 13.2 | | | | | | | | | |
|---|
| 8 | 20.3 | 16.7 | 15.5 | | | | | | | | | |
|---|
| 9 | 18.9 | 16.8 | 18.5 | | | | | | | | | |
|---|
| 10 | 17.2 | 15.2 | 19.0 | | | | | | | | | |
|---|
| 11 | 23.1 | 16.8 | 17.5 | | | | | | | | | |
|---|
| 12 | 19.2 | 16.6 | 18.1 | | | | | | | | | |
|---|
| 13 | 16.1 | 17.1 | 16.2 | | | | | | | | | |
|---|
| 14 | 16.0 | 19.0 | 12.5 | | | | | | | | | |
|---|
| 15 | 16.1 | 18.3 | 14.4 | | | | | | | | | |
|---|
| 16 | 17.7 | 17.0 | 17.3 | | | | | | | | | |
|---|
| 17 | 16.6 | 14.8 | 19.4 | | | | | | | | | |
|---|
| 18 | 17.3 | 15.2 | 18.7 | | | | | | | | | |
|---|
| 19 | 18.9 | 16.7 | 16.8 | | | | | | | | | |
|---|
| 20 | 22.0 | 18.8 | 18.0 | | | | | | | | | |
|---|
| 21 | 19.0 | 20.4 | 16.9 | | | | | | | | | |
|---|
| 22 | 20.3 | 19.3 | 12.3 | | | | | | | | | |
|---|
| 23 | 18.8 | 18.7 | 12.6 | | | | | | | | | |
|---|
| 24 | 16.6 | 16.2 | 12.4 | | | | | | | | | |
|---|
| 25 | 15.8 | 17.8 | 14.3 | | | | | | | | | |
|---|
| 26 | 17.1 | 18.5 | 17.0 | | | | | | | | | |
|---|
| 27 | 18.5 | 18.0 | 18.5 | | | | | | | | | |
|---|
| 28 | 19.7 | 18.2 | 16.4 | | | | | | | | | |
|---|
| 29 | 22.1 | | | | | | | | | | | |
|---|
| 30 | 19.1 | | | | | | | | | | | |
|---|
| 31 | 18.2 | | | | | | | | | | | |
|---|
|
