Titan Corp., the largest supplier of translators and linguists to the U.S. military, had at least 131 personnel or subcontractors killed in Iraq since the March 2003 invasion - the most for any contractor, according to the Labor Department.
The dead numbered 15 in 2003 and at least 116 since 2004. Halliburton Co. units had the second-highest death toll - 61 - including 26 employees and 35 subcontractors. An Iraqi subcontractor for Environmental Chemical Corp., which cleans up ammunition sites, had the third-highest casualties - 22.
Overall, there have been at least 273 contractor deaths, including 23 in 2003, 209 last year and 41 so far this year, according to Labor Department figures. That's over 50 percent more than the 173 deaths of U.K. and allied troops, according to figures compiled by the Brookings Institution in Washington.
"Regardless of the good news and spin from the Iraqi election, the figures show the corner hasn't yet been turned," said Peter Singer, a Brookings analyst who has written on the military's use of private contractors.
"Iraq is just as dangerous as ever, both for U.S. soldiers and for contractors," he said. As of Thursday, 1,519 U.S. personnel have died in Iraq - 139 during the invasion.
"These figures suggest that while contractor deaths were about 5 percent of the 2003's military casualties, they represent about 25 percent of both 2004 and 2005's," said Deborah Avant, associate professor of political science at George Washington University, who has also studied contractor use in Iraq.
"Either contractors are doing more dangerous things or there were more contractors in the theater in 2004," she said.
There are no reliable figures for the number of contractors in Iraq. The Pentagon last year told Missouri Rep. Ike Skelton that about 20,000 personnel were employed by firms providing physical security. That doesn't include contractors working reconstruction projects.
The Joint Chiefs of Staff in May estimated there may be as many as 30,367 contractors in the Middle East and Afghanistan, in addition to the 20,000 providing private security.
The Government Accountability Office is conducting a survey of contractor use in Iraq.
Titan spokesman Wil Williams, citing security and personnel reasons, declined to comment on the company's deaths.
"Our people continue to provide a mission critical service and to perform admirably in a very difficult environment," Titan chief executive Gene Ray said earlier this month.