Chevron Corporation's fourth quarter earnings were down 37 percent from the year-ago period due to weak demand for diesel and gasoline coupled with lower crude oil and natural gas prices
, Chevron said. The energy company said it earned $3.07 billion, or $1.53 per share, during the 2009 quarter, down from $4.9 billion, or $2.44 a share, in the fourth quarter of 2008.

"Earnings decreased in 2009 as a result of lower crude oil and natural gas prices and a decline in refined product sales margins, driven by a weak global economy," said John Watson, Chevron's chairman and CEO. "In this challenging environment, Chevron's successes in operational reliability and cost management made valuable contributions to our bottom line."

Meanwhile, sales and other operating revenue was up to $48 billion, compared to $43 billion in the 2008 quarter.

According to Chevron, worldwide net oil production was 2.78 million barrels per day in the fourth quarter, up from 2.54 million barrels per day in the year-ago quarter.

Over the last few months, crude oil prices have been volatile, rising up near the $80 mark in October and back down to $70 in December.

Meanwhile, diesel prices rose 22.6 cents at the beginning of the fourth quarter, then spent the next seven weeks falling. The fuel saw a slight boost at the end of December.