As if trying to predict the monthly payrolls number wasn't difficult enough, getting September's number correct is almost a lost cause.

The Bloomberg consensus estimate predicts that 150,000 jobs were lost last month, following the creation of 169,000 new jobs in August. The range of estimates is extremely wide, with economists figuring that as few as 25,000 to as many as 350,000 jobs disappeared. The unemployment rate is expected to rise to 5.1% from 4.9%.

"I am expecting a decline of 169,000 jobs but the real question is what is the underlying job growth ex-Katrina," said Michael Gregory, senior economist at Harris Nesbitt. "The changes the Bureau of Labor Statistics has implemented and the strike that occurred at Boeing during the survey week may overestimate September's job losses."

Hurricanes Katrina and Rita, which battered the Gulf Coast recently, left thousands unemployed in Louisiana, Mississippi and elsewhere. Katrina itself, the first of the two storms, destroyed businesses and pushed energy to record prices, and the wide range of forecasts for lost jobs shows that many economists are having a difficult time determining the impact of the storms.

The Labor Department has made changes to the normal payroll survey to account for the Gulf Coast devastation. For instance, according to the Bureau of Labor Statistics Web site:
If there are sample units that BLS is unable to contact in the most heavily impacted disaster areas, the Current Employment Statistics survey will assume the business is not operating and therefore has an employment level of zero. This carries some risk of overstating employment loss.

However, if CES follows its usual imputation procedure for non-respondents, all non-responding units in these areas would have the over-the-month change trend of all other sample units in the estimation cell assigned to them. This assumption, given the present circumstances in the affected areas, is unlikely to be true, and, therefore, following standard imputation procedure would carry a strong risk of understating employment loss.

Traders have seen a mixed bag of economic releases and a handful of companies warning of profit shortfalls heading into the number Friday. Investors were finally seeing the effects of higher energy prices on some companies.

Wendy's ( WEN) said third-quarter same-store sales fell 5% in the U.S. The restaurant operator said same-store sales were hurt by store closings after Hurricanes Katrina and Rita, high gasoline prices and lower consumer spending.

Clorox ( CLX) lowered its earnings forecast for the second quarter to a range of 41 cents to 47 cents a share from its previous outlook of 50 cents to 57 cents a share. The company also cut its full-year earnings forecast, citing rising energy costs.

Hospital operators Tenet Healthcare ( THC) and Universal Health Services ( UHS) have suffered major effects from the hurricanes, and Entergy ( ETR) said costs to repair electrical facilities damaged by Hurricane Rita will probably be $400 million to $550 million.

Not all economists are looking for a big decline. Richard Yamarone, director of economic research at Argus Research, is expecting a decline of 70,000 jobs, but he said it's conceivable the number could actually be positive.

"I do not think any large blue-chip U.S. companies laid anyone off in Louisiana," he said. "You just do not do something like that during a time of a natural disaster. But I do expect to see a large jump in displaced sole proprietors in the household survey."

With that in mind, Yamarone said he "wouldn't be surprised to see the unemployment rate rise to 5.3%, or maybe even higher."

"The equity market has been going through a much needed correction," said Vincent Ambrose, senior trader at Fox Investments. "Most traders will have their positions squared away heading into tomorrow's number because trying to predict the number is almost impossible."

The jobs report, one of the most influential economic indicators the government releases, will arrive at the end of a busy week for traders. Already, the market has gotten the Institute for Supply Management's manufacturing index, which rose unexpectedly for September. Also, the Census Bureau said factory orders rose 2.5%, topping forecasts.

On Wednesday, the ISM's services index for September fell to 53.3 from 65.0 in August, pointing to a slower pace of expansion. A reading above 50 signals growth, but economists expected the number to come in at 60.0. At the same time, the prices-paid component of the index jumped, sparking inflationary concerns.

The latest first-time jobless claims rose 21,000 to 390,000 for the week ended Oct. 1. Economists expected new claims to decline to 350,000 from 356,000 the previous week. On top of all that, the market had to deal with more comments from Federal Reserve officials that indicated the central bank wasn't through hiking rates.

There is uncertainty in this market, but one thing most traders agree on is that whether the jobs number is good or bad, it needs to be taken with a grain of salt.

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