Economic data released Friday morning sent warning signals to Wall Street as the markets retreated.

Consumer sentiment is worsening, according to the consumer sentiment index released by the University of Michigan. The index fell to 87.2 in mid-June from 92.1 at the end of May. Economists had predicted a rise in the index to 93, as the public's concerns about war in Iraq subsided.

Separately, wholesale prices fell 0.3% in May after recording a record drop of 1.9% in April, according to the producer price index released by the Labor Department. Economists had predicted a drop of just 0.2%, according to Briefing.com. The core producer price index, which measures wholesale prices excluding food and energy prices, rose 0.1% in May, after falling 0.9% in April.

The wholesale price index measures the prices of goods sold before they reach consumers, and its last two readings are one reason that Federal Reserve Chairman Alan Greenspan has spoken candidly about deflationary concerns in the economy recently. In light of Friday's reading, the markets are waiting in earnest for the release of May's consumer price index reading, the government's main gauge of price movement in the economy, slated for next Tuesday. Economists are predicting a 0.1% drop in the consumer price index, a marked improvement over April's 0.9% decline.

Amid the negative news, a shrinking U.S. trade deficit reported Friday by the Commerce Department provided a silver lining. The deficit declined 2% to $42 billion in April after widening to $42.9 billion in March, a record high, as the biggest decline in crude oil prices in 13 years helped cut America's foreign oil bill, the government said.

Crude oil prices did fall from their prewar highs near $40 per barrel, reaching $25.24 on April 29. But since April, they have been rising steadily in the war's aftermath. On Wednesday, they reached $32.36 per barrel, their highest close since March 17, after OPEC decided to leave production quotas unchanged at its meeting in Doha, Qatar. According to Fadel Gheit, a senior energy analyst at Fahnestock & Co., crude oil prices over $30 put a major strain on the U.S. economy.

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