When the Ebola crisis began spiraling out of control this summer, donors pledged nearly $3 billion to help rein it in. But some aid groups paid only a fraction of what they had promised, according to a new study.

The study examined thousands of international pledges and donations, based on data from the U.N.’s Office for the Coordination of Humanitarian Affairs. While many countries and organizations made generous pledges to curb the outbreak, several failed to deliver on their promises. The United States pledged nearly $1 billion, and paid almost all of it. The World Bank, on the other hand, pledged closer to $200 million, and has delivered on only about half of that. The Paul G. Allen Family Foundation proudly announced its commitment of $100 million to Ebola—but appears to have paid only $55 million.

Here’s a table of those figures, from the paper:

Ebola is now fading away in West Africa, but an estimated 8,000 people have succumbed to the virus since mid-March. It is still unclear why, even as the epidemic raged, some donors failed to come up with the cash. It probably didn’t help that the U.N. kept sending mixed messages about how much money it needed. Requests for $4.8 million in April became $71 million by August, and that figure ballooned to $1.5 billion by mid-November. Here’s an illustration of the ebb and flow of the Ebola epidemic: