Released on November 23, 2005
(Next Release on November 30, 2005)

Learning from History
There has been much speculation about the year-on-year decreases in weekly petroleum demand data in the weeks following the production shut-ins and subsequent price increases accompanying Hurricanes Katrina, Rita, and Wilma. Total petroleum products supplied for the 4 weeks ending September 30, 2005 were 19,940 thousand barrels per day, almost three percent lower than the same four-week average last year.

However, EIA has cautioned that weekly data may have overstated somewhat the degree of decline in product supplied, due to its preliminary nature and reporting difficulties experienced by some respondents. In fact, it is not uncommon for EIA's monthly petroleum data to show higher demand levels than estimated from weekly data.

Recently, September 2005 monthly data (in the November Petroleum Supply Monthly) were released. As anticipated, these data show that both monthly gasoline demand and total petroleum product demand were higher than the weekly estimates available earlier. September total petroleum product demand and total motor gasoline demand in the monthly data are each more than 100 thousand barrels per day higher than the monthly-from-weekly prorated averages. Monthly September 2005 gasoline and total products were both 1.5 percent lower, respectively, than the comparable year-ago demand estimates published in the September 2004's Petroleum Supply Monthly. However, this did show a marked narrowing of the gap versus the monthly-from-weekly averages calculated for September 2005, which showed demand at 2.6 percent lower for gasoline and 2.1 percent lower for total petroleum products versus September 2004.

The monthly total petroleum product supplied data has been higher than the monthly-from-weekly average 63 percent of the time since January 2000, with an average change of 121 thousand barrels per day. Motor gasoline product supplied has also been revised upward 62 percent of the time over this period with an average change of 38 thousand barrels per day, while total distillate demand has also seen a small average move upwards. So the trend has definitely been for weekly data to underestimate demand compared to the more accurate monthly data. Just looking from January 2004 through August 2005, product supplied data for total petroleum products were adjusted up 70 percent of the time, with an average change of 201 thousand barrels per day.

This leads to two questions. Why is the monthly data more accurate than weekly data, and why generally are the monthly data revised upwards? The weekly data is collected through a sample of respondents, while monthly data collects data from the whole universe of respondents. In aftermath of the hurricanes, it is possible that logistical problems associated with company operations may have affected data reporting on the weekly surveys.

Both the monthly and weekly surveys are very valuable in their own ways, but they each have their drawbacks as well. The weekly survey serves a valuable purpose in providing the most current information on trends in oil markets, but the monthly survey provides the complete picture. Generally, the longer period to report monthly data results in higher estimates of refinery production and imports.

So, what do the latest monthly data tell us about current oil market conditions? For gasoline, it indicates that demand did not drop as much due to high prices as preliminary data may have suggested, and with weekly data now showing some growth compared to last year, it confirms EIA's expectations that gasoline demand is still growing relative to year-ago levels, albeit by less than previous trend rates.

Residential Heating Oil Prices Drop Further; Residential Propane Prices Show Slight Decrease
Residential heating oil prices decreased for the period ending November 21, 2005. The average residential heating oil price dropped 3.5 cents from last week to reach 243.1 cents per gallon, an increase of 40.6 cents from this time last year. Wholesale heating oil prices decreased 4.3 cents to reach 173.1 cents per gallon, an increase of 21.3 cents compared to the same period last year.

The average residential propane price decreased 0.6 cent, to 193.9 cents per gallon. This was an increase of 25.1 cents over the 168.8 cents per gallon average for this same time last year. Wholesale propane prices increased 1.5 cents per gallon, from 104.7 cents to 106.2 cents per gallon. This was an increase of 9.5 cents from the November 22, 2004 price of 96.7 cents per gallon.

U.S. Retail Gasoline and On-Highway Diesel Prices Decrease for Seventh Week
The U.S. average retail price for regular gasoline dropped by 9.5 cents to 220.1 cents per gallon, falling for the seventh week in a row; this price was still 25.3 cents higher than this time last year. Retail prices have fallen by almost 73 cents per gallon in the past seven weeks. Prices were down throughout the country, with the West Coast seeing the largest regional decrease of 11.4 cents to 243.3 cents per gallon, the highest regional price in the country. The Midwest again had the lowest regional price in the country, falling 9.1 cents to 208.7 cents per gallon. East Coast prices fell by 8.9 cents to 220.6 cents per gallon.

Retail diesel fuel prices fell 8.9 cents to reach 251.3 cents per gallon, the lowest price since August 8, 2005. The U.S. average retail diesel price has fallen 64.4 cents per gallon during the last four weeks. Prices were down throughout the country, with the Rocky Mountains seeing the largest regional decrease of 11.2 cents to 265.4 cents per gallon, which remained highest regional average price in the country. Midwest prices were down 9.8 cents to 247.7 cents per gallon, the lowest regional price in the nation. West Coast prices averaged 265.2 cents per gallon after falling 8.6 cents.

Propane Inventories Report Weekly Gain
U.S. inventories of propane continued on a roller-coaster path last week with a weekly gain that pushed inventories up 1.0 million barrels to 68.5 million barrels as of November 18, 2005. Despite the surprise gain last week, inventories so far this month are down about 0.9 million barrels. With nearly two weeks remaining for November data, U.S. inventories still have plenty of time to surpass the 5-year average stockdraw for this month that averaged 1.9 million barrels. Imports again played a leading role in last week's gains across all the major areas compared with the prior week. East Coast inventories posted a 0.3-million-barrel increase, while inventories in the Gulf Coast rose 0.8 million barrels during this same time. Midwest inventories remained flat last week, while the combined Rocky Mountain/West Coast regions saw the only inventory decline, measuring 0.1 million barrels. Propylene non-fuel use inventories remained unchanged at 3.7 million barrels, accounting for a slightly smaller 5.4 percent share of total propane/propylene inventories compared with 5.5 percent share from the previous week.

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