The world's 100 top arms-producing countries sold over $400 billion worth of arms in 2009, according to new data released Monday by the Stockholm International Peace Research Institute (SIPRI), amounting to an 8 percent increase over the previous year despite the ravages of the global economic downturn.

United States-based companies outpaced all others in producing the most arms, according to the data.  Eight of the top ten biggest arms dealers are based in the U.S., including Lockheed Martin (the largest arms producer in the world), Boeing, Northrup Grumman, GE, Raytheon, and others.

"Arms sales of the Top 10 arms-producing companies approached $228 billion, which is 56.9 per cent of the SIPRI Top 100 total arms sales in 2009," according to a report released along with the data.

Much of the spending is due to U.S. war efforts in Iraq and Afghanistan.

"US government spending on military goods and services is a key factor in arms sales increases for US arms-producing and military services companies and for Western European companies with a foothold in the US arms and military services market," said Susan Jackson, a SIPRI analyst.

Over 60 percent of the profit from arms sales by SIPRI's "Top 100," accounting for $247 billion, is produced by US-based arms manufacturers.

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