March 5 (Bloomberg) -- OPEC will reduce crude-oil shipments by 1.9 percent in the month ending March 21 as producers use record cuts to stem falling prices, according to tanker-tracker Oil Movements.

The Organization of Petroleum Exporting Countries, producer of more than 40 percent of the world’s oil, will load 22.67 million barrels a day in the period, down from 23.1 million a day in the month ended Feb. 21, Oil Movements said in a report today. That would be the lowest volume since 2004.

The group is still as much as 30 percent short of full compliance with announced reductions totaling 4.2 million barrels a day since September, according to the consultant. Members including Algeria, Venezuela and Qatar have said further reductions may be needed when the organization meets March 15.

“They’re getting there, but there’s still going to be a big gap when the group meets to decide what to do next,” Oil Movements founder Roy Mason said by phone from Halifax, U.K.

OPEC agreed Dec. 17 on output caps to reduce supplies in January by 2.2 million barrels a day from December levels. That followed pledges to remove 2 million barrels a day in the fourth quarter of last year.

Shipments from the Middle East will fall 1.3 percent to 16.27 million barrels a day in the four weeks to March 21, the report said. A total of 452.14 million barrels of crude will be on board tankers on March 21, an increase of 1.3 percent from the month before, when 446.16 million barrels were on route.

Oil Movements combines reports from shipbrokers on tanker rentals with its own mathematical models to calculate how much crude is being shipped.

To contact the reporters on this story: Grant Smith in London at gsmith52@bloomberg.net;

Last Updated: March 5, 2009 11:30 EST