Customer Service
800-331-3332 or 312-930-2316

|
Jan |
Feb |
Mar |
Apr |
May |
Jun |
Jul |
Aug |
Sep |
Oct |
Nov |
Dec |
Yearly |
|
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1990 | 15.4 | 12.1 | 9.7 | 17.2 | 17.2 | 15.3 | 12.6 | 37.1 | 14.1 | 31.2 | 13.5 | 27.2 |
18.5 |
| 1991 | 32.0 | 31.5 | 34.5 | 21.9 | 18.3 | 25.9 | 27.3 | 17.7 | 21.8 | 13.4 | 13.5 | 13.8 |
22.6 |
| 1992 | 26.6 | 14.0 | 11.8 | 12.1 | 9.2 | 10.5 | 17.3 | 16.8 | 16.5 | 9.1 | 25.0 | 10.3 |
14.9 |
| 1993 | 11.2 | 16.5 | 15.7 | 23.0 | 33.0 | 23.1 | 27.6 | 44.8 | 39.2 | 26.7 | 25.1 | 21.4 |
25.6 |
| 1994 | 26.0 | 24.3 | 21.0 | 23.2 | 34.9 | 27.3 | 17.1 | 21.3 | 19.1 | 17.2 | 17.1 | 23.0 |
22.6 |
| 1995 | 22.9 | 22.6 | 39.3 | 33.7 | 39.2 | 26.6 | 19.8 | 29.3 | 21.0 | 13.2 | 17.6 | 8.7 |
24.5 |
| 1996 | 16.7 | 18.0 | 16.8 | 22.0 | 10.8 | 19.6 | 21.4 | 14.6 | 15.7 | 15.9 | 21.0 | 15.2 |
17.3 |
| 1997 | 24.3 | 27.6 | 15.4 | 18.7 | 18.5 | 16.9 | 30.2 | 28.9 | 25.9 | 38.8 | 37.8 | 35.4 |
26.5 |
| 1998 | 35.0 | 57.7 | 40.0 | 19.9 | 32.2 | 28.9 | 21.0 | 25.0 | 24.2 | 26.9 | 25.6 | 24.3 |
30.1 |
| 1999 | 21.8 | 34.6 | 23.3 | 21.2 | 24.6 | 17.3 | 19.1 | 15.5 | 32.7 | 32.7 | 18.7 | 14.6 |
23.0 |
| 2000 | 18.8 | 32.3 | 15.8 | 16.1 | 15.4 | 11.4 | 9.7 | 11.2 | 9.2 | 14.6 | 12.8 | 11.3 |
14.9 |
| 2001 | 11.3 | 11.9 | 14.5 | 14.0 | 19.4 | 14.2 | 12.4 | 16.4 | 40.1 | 39.4 | 15.7 | 21.6 |
19.2 |
| 2002 | 23.1 | 19.4 | 12.3 | 19.4 | 14.1 | 17.4 | 22.9 | 18.4 | 13.3 | 19.8 | 19.9 | 20.0 |
18.3 |
| 2003 | 18.0 | 21.0 | 13.9 | 13.3 | 15.1 | 13.1 | 26.6 | 24.2 | 22.4 | 23.9 | 31.7 | 12.6 |
19.6 |
| 2004 | 41.5 | 25.2 | 24.7 | 60.7 | 39.9 | 34.6 | 32.5 | 20.6 | 32.0 | 32.0 | 25.7 | 42.9 |
34.4 |
| 2005 | 26.3 | 29.7 | 23.5 | 22.8 | 21.7 | 13.6 | 14.3 | 16.4 | 18.5 | 20.8 | 14.3 | 25.0 |
20.6 |
| 2006 | 30.7 | 29.9 | 27.6 | 85.9 | 57.0 | 62.4 | 41.6 | 35.3 | 45.1 | 34.5 | 23.1 | 33.8 |
42.2 |
| 2007 | 30.9 | 25.3 | 26.7 | 19.2 | 20.7 | 24.3 | 20.1 | 37.0 | 17.0 | 23.1 | 36.9 | 22.7 |
25.6 |
| 2008 | 22.3 | 23.3 | 58.0 | 32.7 | 36.0 |
34.5
|
|||||||
| Mean | 23.9 | 25.1 | 23.4 | 26.2 | 25.1 | 22.4 | 21.9 | 23.9 | 23.8 | 24.1 | 21.9 | 21.3 |
|
| High | 41.5 | 57.7 | 58.0 | 85.9 | 57.0 | 62.4 | 41.6 | 44.8 | 45.1 | 39.4 | 37.8 | 42.9 | |
| Low | 11.2 | 11.9 | 9.7 | 12.1 | 9.2 | 10.5 | 9.7 | 11.2 | 9.2 | 9.1 | 12.8 | 8.7 |