Worldwide weapons deals also dropped in the year, the library's Congressional Research Division report said, The New York Times reported Monday.
U.S. sales dropped from $38.1 billion in 2008 to $22.6 billion in 2009, a significant decline. But the United States still commands the lion's share of the market with 39 percent of global weapons sales last year.
Overall, weapons sales fell 8.5 percent to $57.5 billion in the year, compared to 2008.
In 2009, Russia's weapons sales came to $10.4 billion, while sales from France amounted to $7.4 billion, putting their sales volume in second and third place, respectively.
But 2008, presumably a tough business year, saw a sharp increase in U.S. weapons sales compared to 2007, which means a normal business cycle is also shaping the industry.
The report said the industry is still robust, but governments in 2009 chose "to defer the purchase of major systems … (during a) severe international recession."
On the other hand, "Some nations chose to focus on completing the integration into their militaries of major weapons systems they had already purchased," wrote Richard Grimmett, author of the study.
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