Far fewer people died or were left homeless by last year’s devastating earthquake than claimed by Haitian leaders, a report commissioned by the U.S. government has concluded — challenging a central premise behind a multibillion-dollar aid and reconstruction effort.

The report, a copy of which was obtained Monday by The Associated Press, estimates that the death toll was between 46,000 and 85,000, far below the Haitian government’s official figure of 316,000. The report was prepared for the U.S. Agency for International Development but has not yet been publicly released.

Haitian authorities stood by the figures they released last year.

The report has inconsistencies, however, and won’t be released publicly until they are resolved, U.S. State Department spokeswoman Preeti Shah told the AP.

“The first draft of the report contained internal inconsistencies with its own findings,” Shah said in a telephone interview from Washington. “We are reviewing these inconsistencies … to ensure information we release is accurate.”

Shah would not elaborate or say whether the report could change significantly once the inconsistencies are resolved.

Haitian government officials said they had not seen the report and could not discuss it.

Based on a statistical sampling from a hard-hit section of downtown Port-au-Prince, the report also estimates that about 895,000 people moved into temporary settlement camps around the capital after the quake and that no more than 375,000 of those are still living under tarps and in tents and wooden shanties.

Those figures conflict with numbers provided by the U.N. International Organization for Migration, which says the camp population reached 1.5 million after the quake and that there are still 680,000 in settlement camps around the capital.

The report also says there was less rubble than previously estimated. Immediately after the earthquake, the U.S. Army Corps of Engineers reported about 20 million cubic meters (26 million cubic yards) of debris, enough to fill the Louisiana Superdome five times. But the study concluded that the total is less than half that amount.

The discrepancies are more than academic: The huge death toll and widespread destruction helped justify an international outpouring of aid for the impoverished Caribbean country, including $5.5 billion pledged during a March 2010 U.N. donor’s conference.

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