The public health school won’t publish a preliminary report this month on the total number of deaths in Puerto Rico following Hurricane Maria.

Lynn Goldman, the dean of the Milken Institute School of Public Health, told The New York Times that though the school promised that an initial report would be released in May, researchers are “still acquiring data.” She said the preliminary review – costing about $305,000 – will now be released sometime this summer, followed by a more comprehensive analysis in early 2019.

The governor of Puerto Rico initially ordered a review of the death toll in the island nation in February amid criticism of the government’s management of the disaster. The government estimated 62 people had died in the aftermath of the hurricane – which devastated the island last fall – but other reports, including an investigation by The New York Times, approximated the number closer to 1,000.

The latest death toll estimates clock in at roughly 4,600, according to a study released Tuesday by independent researchers at the Harvard T.H. Chan School of Public Health and other schools.

Goldman said researchers are running behind schedule because the University unexpectedly had to deal with different tax laws while drafting a contract with the Puerto Rican government, The New York Times reported.

Carlos Mercader, the executive director of the Puerto Rico Federal Affairs Administration, told The Times that both the new independent study and the GW review will help the island “better prepare for future natural disasters and prevent lives from being lost.”