| MONTH | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | MO. AVG. | |
| JAN. | $2.344 | $9.978 | $2.555 | $4.988 | $6.150 | $6.213 | $11.431 | $5.838 | $7.172 | $6.297 | |
| FEB. | $2.610 | $6.293 | $2.006 | $5.660 | $5.775 | $6.288 | $8.400 | $6.917 | $7.996 | $5.772 | |
| MAR. | $2.603 | $4.998 | $2.388 | $9.000 | $5.150 | $6.304 | $7.112 | $7.547 | $8.930 | $6.004 | |
| APR. | $2.900 | $5.384 | $3.472 | $5.146 | $5.365 | $7.323 | $7.233 | $7.558 | $9.578 | $5.995 | |
| MAY. | $3.089 | $4.891 | $3.319 | $5.123 | $5.935 | $6.748 | $7.198 | $7.508 | $11.280 | $6.121 | |
| JUN. | $4.406 | $3.738 | $3.420 | $5.945 | $6.680 | $6.123 | $5.925 | $7.591 | $11.916 | $6.194 | |
| JUL. | $4.369 | $3.182 | $3.278 | $5.291 | $6.141 | $6.976 | $5.887 | $6.929 | $13.105 | $6.129 | |
| AUG. | $3.820 | $3.167 | $2.976 | $4.693 | $6.048 | $7.647 | $7.042 | $6.110 | $9.217 | $5.636 | |
| SEP. | $4.618 | $2.295 | $3.288 | $4.927 | $5.082 | $10.847 | $6.816 | $5.430 | $8.394 | $5.744 | |
| OCT. | $5.312 | $1.830 | $3.686 | $4.430 | $5.723 | $13.907 | $4.201 | $6.423 | $7.472 | $5.887 | |
| NOV. | $4.541 | $3.202 | $4.126 | $4.459 | $7.626 | $13.832 | $7.153 | $7.269 | $6.469 | $6.520 | |
| DEC. | $6.016 | $2.316 | $4.140 | $4.860 | $7.976 | $11.180 | $8.318 | $7.203 | $6.501 | ||
| YR.'S AVG. | $3.886 | $4.273 | $3.221 | $5.377 | $6.138 | $8.616 | $7.226 | $6.860 | $9.230 | $6.067 | |
| 1st Qtr. | $2.519 | $7.090 | $2.316 | $6.549 | $5.692 | $6.268 | $8.981 | $6.767 | $8.033 | $6.024 | |
| 2nd Qtr. | $3.465 | $4.671 | $3.404 | $5.405 | $5.993 | $6.731 | $6.785 | $7.552 | $10.925 | $6.103 | |
| 3rd Qtr. | $4.269 | $2.881 | $3.181 | $4.970 | $5.757 | $8.490 | $6.582 | $6.156 | $10.239 | $5.836 | |
| 4th Qtr. | $5.290 | $2.449 | $3.984 | $4.583 | $7.108 | $12.973 | $6.557 | $6.965 | $6.971 | $6.320 |