(Updates stock prices to reflect values at the close of trading Monday.)

Is it demand? Is it the dollar? Is it growing doubts about a near-term global economic recovery? Is it all of the above? Whatever reason analysts want to point to, today crude futures slipped again, marking the fourth straight day that prices have fallen.

Light, sweet crude for August delivery slumped another $2.68 today to settle at $64.05 per barrel on the New York Mercantile Exchange. That came after a tumultuous day of trading that saw the contract dip more than $3 to go as low as $63.40 earlier. Last week, crude was stretching beyond the $73 mark.

Stocks

continued showing mixed returns in the afternoon.

Many stocks throughout the oil sector were still in negative territory by the close of trading Monday, though some had inched upwards following early plunges.

Exxon Mobil

(XOM) - Get Report

and

ConocoPhillips

(COP) - Get Report

finished down 1.3% and 0.3%, respectively.

Chevron

(CVX) - Get Report

finished off 0.4%, or 28 cents, at $64.14.

Petro-Canada

( PCZ) saw its shares plummet 6.5%, or $2.36, to $33.93 today.

In positive territory, ADSs for

China Petroleum & Chemical

(SNP) - Get Report

closed up 2.8%, or $2.10, at $76.86.

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