Updated from 2:58 p.m. EST

Crude oil prices fell another 1% Tuesday, closing below the $50-a-barrel level Monday for the first time in a month.

The December futures contract lost 51 cents to $49.62 in regular trading on the Nymex. The contract had traded below the key level Monday, but closed just above $50.

Prices are down more than 10% since last Wednesday when U.S. inventory data showed healthy gains in oil and gasoline stocks, easing short-term supply concerns, which have dogged the market since Hurricane Ivan disrupted production in the Gulf of Mexico in September. Fresh weekly data will be released tomorrow morning.

Traders also appear to have written off the possibility of a strike in Nigeria later this month.

Until the recent correction, prices had hit record highs on a regular basis for months, topping out at more than $55 a barrel two weeks ago.

The recent decline is not the first in the year-long rally. Prices fell about the same amount in July after OPEC announced the first of three increases in its official production ceiling. Prices recovered and resumed their climb in August.