Sept. 5 (Bloomberg) -- U.S. stock-index futures tumbled, adding to the worst week for global equities since 2002, as the nation's unemployment rate reached the highest level in five years and deepened concern that the world economy is slowing.

Bank of America Corp., Apple Inc. and DuPont Co. all retreated more than 1 percent after the government said payrolls shrank by a 84,000 in August, more than economists forecast. Merrill Lynch & Co. lost 5.4 percent, Barclays Plc sank 5 percent in London and Mizuho Financial Group Inc. tumbled 6.4 percent in Japan as Goldman Sachs Group Inc. advised clients to sell Merrill shares on concern the bank may post more writedowns. Declines from Tokyo to the U.K. helped send the MSCI World Index down 5.5 percent this week.

Stocks ``aren't likely to go up until we see some kind of turn in the economy and that turn wasn't in today's numbers,'' said John Davidson, president of PartnerRe Asset Management Corp., which oversees $12 billion in Greenwich, Connecticut. ``Earnings expectations are going to have to be revised lower.''

Treasuries rose and the dollar fell against the yen. Standard & Poor's 500 Index futures expiring in September lost 12.80 points, or 1 percent, to 1,223.8 at 8:35 a.m. in New York. Dow Jones Industrial Average futures lost 107 to 11,093. Nasdaq- 100 Index futures dropped 19.75 to 1,756.

The S&P 500, the benchmark index for American equities, lost 3.6 percent so far this week and is down 16 percent in 2008. Today's report showing an unemployment rate of 6.1 percent added to concern that the worst housing slump since the Great Depression and more than $500 billion in credit losses and writedowns at global banks are dragging the nation into a recession. Commodities producers tumbled amid concern slowing growth will curb demand for oil and metals.

`Bear Market'

``We're clearly in a bear market,'' Simon Moss, who manages the equivalent of $4.1 billion as investment director of U.S. equities at Scottish Widows Investment Partnership in Edinburgh, said in a Bloomberg Television interview. ``There is no doubt the economy is slowing.''

Stocks in Europe and Asia fell today on concern weakening economic growth will curb earnings at semiconductor makers while credit-related losses at banks increase.

This week's losses threatened to erase the S&P 500's rebound from an almost three-year low set on July 15. The index is up 1.8 percent since then after rebounding as much as 7.4 percent.

Merrill Lynch, down 51 percent this year in New York trading, sank $1.41 to $24.80. Goldman added the company to its ``conviction sell'' list and lowered its share-price projection by 23 percent to $22.

Merrill Valuation

``Merrill currently trades at the highest price-to-book multiple in our large-cap brokerage universe, despite having some of the most significant exposures to troubled assets such as CDOs, mortgages and leveraged loans,'' analysts led by William Tanona wrote. ``With these markets still under pressure, we believe additional writedowns and book value deterioration will continue to plague the stock.''

New York-based Merrill, battered by more than $50 billion of credit market losses and writedowns, has sold mortgage-linked assets to reduce risk and free up capital. The company trades at 1.22 times book value, compared with 0.91 for Citigroup Inc., the only other firm that's lost more from the credit market crunch, according to data compiled by Bloomberg.

Exxon Mobil Corp. slid 24 cents to $75.90. Chevron Corp., the second-largest U.S. oil company, declined 72 cents to $80.50. Crude oil for October delivery fell as much as $2.13 to $105.76 a barrel in New York as the dollar gained, curbing demand for commodities as a currency hedge.

SanDisk Corp. jumped 23 percent to $16.51. Samsung Electronics Co. said it may buy the memory-card maker in what would be the South Korean company's biggest acquisition. Samsung, which is the world's second-largest chipmaker after Intel Corp., said it's considering various options, including an acquisition.

UST Inc. added 23 percent to $66.55. Altria Group Inc., largest U.S. cigarette maker, is in talks to buy the nation's biggest snuff producer for more than $10 billion, the New York Times reported, citing people with knowledge of the discussions who weren't identified.

To contact the reporter on this story: Lynn Thomasson in New York at lthomasson@bloomberg.net.

Last Updated: September 5, 2008 09:16 EDT