The Pentagon has records for fewer than half of the firearms the United States dispensed to partner forces in Afghanistan and Iraq since the Sept. 11, 2001, terrorist attacks, the New York Times reported Wednesday.

A compilation of Pentagon contract records related to the proliferation of rifles, pistols, machine guns, and associated attachments and ammunition found that the Pentagon provided more than 1.45 million firearms to security forces in Afghanistan and Iraq over a 14-year span. Those transfers were part of Defense Department small arms contracts totaling $4 billion. The Pentagon issued over $40 billion in total contracts, according to the report.

The transfers included more than 978,000 rifles, 266,000 pistols, and nearly 112,000 machine guns, according to the data obtained through Freedom of Information Act requests. The report was compiled by Iain Overton, a former BBC reporter who is now the executive director of Action on Armed Violence, a London-based charity group that advocates against weapons proliferation.

Pentagon data shows that the U.S. transferred over 700,000 small arms to Iraq and Afghanistan—an amount accounting for only 48 percent of the total arms supplied by the U.S. government.

The Pentagon said the gap between the counts is in part because the U.S. military was attempting to build up two governments that were both at war in the wake of the 9/11 terrorist attacks.

"Speed was essential in getting those nations’ security forces armed, equipped, and trained to meet these extreme challenges," Mark Wright, a Pentagon spokesman, wrote in an email to the Times. "As a result, lapses in accountability of some of the weapons transferred occurred."

Wright said the Pentagon’s practices have since improved, and that to confirm "that equipment is only used for authorized purposes," its representatives "inventory each weapon as it arrives in country and record the distribution of the weapon to the foreign partner nation."

Still, Wright said that once a U.S. weapon is distributed to another force, "It is their responsibility to account for that weapon."

The New York Times noted, "Anyone who has served in a military unit knows that documenting who received what weapon is both a fundamental task and a habit that fits easily into a routine. It takes no more time than issuing a uniform to a soldier or feeding him a meal. But often the Pentagon did not require these steps."