The move comes one week after the coalition, known as the International Security Assistance Force, acknowledged in response to inquiries by The Associated Press that it had incorrectly reported a 7 percent drop in Taliban attacks in 2012 compared to 2011. In fact, there was no decline at all, ISAF officials now say.

The mistake, attributed by ISAF officials to a clerical error, called into question the validity of repeated statements by allied officials that the Taliban was in steep decline.

Anthony Cordesman, a close observer of the war as an analyst at the Center for Strategic and International Studies, said it had been clear for months that ISAF’s figures were flawed.

“The truth is they should not have published them in the first place,” he said. “A great many people realized from the start that it was a meaningless measurement” because it implies that in order to succeed the Taliban has to keep attacking rather than gaining ground by influencing ordinary Afghans. It’s that influence which needs to be overcome in order to ensure the viability of the Afghan government.

“Over the last year it has become clearer and clearer that not only was the measurement meaningless, but it became embarrassing because there weren’t any (ISAF and Afghan) gains,” he added, noting that Taliban attacks last year were more numerous than in 2009, before President Barack Obama sent an extra 30,000 U.S. “surge” troops.

“Basically speaking, we’ve ended up — after the surge and three more years of fighting — with absolutely nothing that we can tell ourselves that shows the level of progress we did or did not achieve,” Cordesman said.

The U.S. and its ISAF allies have pledged to end their combat mission by the end of next year, and while they are likely to leave at least several thousand troops to help train Afghan troops, the Afghans are to assume the lead role for security across the entire country this spring, when the Taliban typically step up their attacks.

There are now about 66,000 U.S. troops in Afghanistan.

Statistical measures of battlefield progress have long been a point of dispute, not only in Afghanistan but also in Iraq. The disputes typically are a combination of doubt about the numbers themselves and about what they mean.

Jamie Graybeal, a spokesman for ISAF’s headquarters in Kabul, said Tuesday that the coalition has lost confidence in the reporting system that produced its figures on “enemy-initiated” attacks. That is mainly because more combat operations are being performed by Afghan forces, out of view of American and allied troops. That means ISAF has diminishing control over the mechanics of collecting the data.

“We have determined that our databases will become increasingly inaccurate in reflecting the entirety of enemy initiated attacks,” Graybeal said in a written statement.

“Additionally, we have come to realize that a simple tally of (attacks) is not the most complete measure of the campaign’s progress,” he said. “At a time when more than 80 percent of the (attacks) are happening in areas where less than 20 percent of Afghans live, this single facet of the campaign is not particularly accurate in describing the complete effect of the insurgency’s violence on the people of Afghanistan.”

Taliban insurgents have been pushed out of many population centers and have failed to regain territory they held before the surge of U.S. troops in 2010. But they are expected to test Afghan forces as U.S. and allied troops withdraw.

Coalition officials, including Obama administration officials, had previously cited the reported 2012 drop in Taliban attacks as a sign that the insurgency was in decline and that the Afghans could take on more of the fighting burden.

Last Tuesday, on his final day as defense secretary, Leon Panetta indicated that he was disappointed in the mix-up. The Pentagon on Tuesday said it was leaving it to ISAF to explain the decision to stop reporting attack figures.

Graybeal said ISAF will continue to track Taliban attacks that are observed and recorded by ISAF troops. But it will not track and report on the totality of attacks — including those directed at Afghan forces.

The erroneous ISAF report of a decline in 2012 attacks came to light after ISAF removed from its website a set of statistics that included its tally of “enemy initiated attacks,” which it had said declined by 7 percent. When the AP inquired about the missing figures, ISAF said they had been removed because they contained errors.

Initially, ISAF said it would correct and republish the statistics, but on Tuesday Graybeal said the corrected 2012 figures will not be put back on its web site.

That raises questions about the Pentagon’s most recent report to Congress on progress toward stabilizing Afghanistan, which used the coalition’s figures on enemy attacks as its main measure of insurgent violence. The report also cautioned in a footnote, however, that the attack figures have “a number of limitations” and should not be used by themselves as a reliable indication of violence levels in Afghanistan.

A Pentagon spokesman, Navy Cmdr. William Speaks, said the issue of counting Taliban attacks will be addressed in the next report to Congress, due by April 30, “and the errors in these figures will be explained.” That report will cover developments in Afghanistan from October 2012 through March 2013.

The previous report to Congress, covering the period from April 2012 through September 2012, said ISAF and Afghan forces had continued to “degrade the cohesion and capability” of the insurgency, while acknowledging that the militants were still capable of carrying out high-profile attacks like a stunning assault on Camp Bastion on Sept. 14 in which 15 Taliban fighters breached the security perimeter, killed two U.S. Marines and destroyed six U.S. Marine aircraft.