The Pentagon is judging success or failure in Iraq by more than daily casualty and attack statistics.
It recently set up an "Iraq Room" where officers study and measure a long stream of data, to produce what the Pentagon calls "metrics" that tell Defense Secretary Donald H. Rumsfeld whether the Iraq campaign is headed in the right direction.
"The secretary is big on metrics," said a senior Pentagon official. "He's a metrics kind of guy. He believes you cannot tell how you are doing unless you are taking measurements."
Besides casualties and insurgent attacks, analysts look at the number of arrests, detainees' identities and roles in the insurgency, and the locations.
"It's kind of a fusion center with a lot of policy analysts who sift through an enormous amount of data and information that's coming in from commanders," said Rumsfeld spokesman Larry Di Rita.
Mr. Di Rita said the Iraq Room does not issue reports, per se, but its measurements appear in regular briefings to the secretary.
Teams study intelligence estimates on the number of insurgents -- currently 12,000 to 20,000 -- and how many are entering the country versus how many are native Iraqis.
On the civilian side, they look at the pace of construction projects for schools, clinics, electrical grids or manufacturing plants. They also look at political developments.
One development came Friday when Ahmed Abdul Ghafour al Samarri, a Sunni cleric in the influential Association of Muslim Scholars, reversed course and urged Iraqis to join the Iraqi Security Forces, the Associated Press reported from Baghdad.
The Pentagon's Iraq Room is tabulating the metrics that policy-makers say are virtually impossible to develop for the broader global war against Islamist terrorists. No one knows for sure how many al Qaeda operatives are replaced worldwide for each one killed or captured.
But in a defined area such as Iraq, metrics come more easily.
Gen. John Abizaid, the top commander in Iraq, said intelligence shows more foreign fighters are infiltrating the country because some Iraqis are refusing to take part in attacks on fellow Iraqis.
The Iraq Room was set up several months ago inside the Joint Staff, the support group for the Joint Chiefs that conducts analysis, plans operations and maintains a Pentagon linkage with commands around the world.
"We have a room here, the Iraq Room, where we track a whole series of metrics," Mr. Rumsfeld said on National Public Radio last week. "Some of them are inputs and some of them are outputs, results and obviously the inputs are easier to do and less important, and the outputs are vastly more important and more difficult to do."
The numbers for March show the U.S. campaign may be going in the right direction. U.S. service member deaths, at 35, were the lowest in a year. The number of daily attacks is drifting below 40, and many of those attacks are ineffective, military officials say.