At the U.S. Fish and Wildlife Service (FWS) headquarters in Falls Church, Virginia, sits a treasure trove of data. As part of a program called TAILS (Advanced Tracking and Integrated Logging System), FWS keeps records of consultations between its field agents and other federal agencies whose proposed projects might affect federally protected species. These consultations, mandated by Section 7 of the Endangered Species Act (ESA), document which federal agencies have authorized or funded projects—such as new oil and gas drilling—and whether a given project poses any risk to threatened or endangered species. Gary Frazer, assistant director for endangered species at FWS, calls the TAILS data “pretty dry bureaucratic stuff.”

But Ya-Wei Li, senior director of endangered species conservation at the Washington, D.C.–based nonprofit Defenders of Wildlife, didn’t think so. In the spring of 2014, he brought his whooping crane–shaped thumb drive to FWS headquarters to download the information. He and his colleagues hoped to find out whether common criticisms of Section 7—that the consultation process is onerous, it takes too long, and it’s bad for the economy—were borne out in the data. The results of their year-and-a-half-long analysis, out today in the Proceedings of the National Academy of Sciences, suggest that many of the reproaches of the process are unfounded.

FWS is frequently called to testify before Congress about the economic impact of the ESA, and lawmakers have floated several proposals to change it by exempting certain actions from review or restricting its funding. The act “is a very public controversial piece of legislation that goes before Congress every session with proposals to revise it, and that’s because of the perception about how it’s applied,” says Mark Schwartz, a conservation biologist at the University of California, Davis.

FWS doesn’t have the staff to analyze determinations made by the eight regional offices across the country that end up in the TAILS data—which could help the agency determine how to implement the act consistently across the country and find out whether doing more consultations helps protect listed species.

Li and his team looked at 88,290 FWS consultations conducted between January 2008 and April 2015 and found that over that time, the median number of consultations declined by more than 1000 a year. Just two consultations, or just 0.03%, resulted in a jeopardy finding—meaning a project could put a threatened or endangered species at risk—compared with 17.5% between 1987 and 1991 found in a previous study. No project was stopped or changed significantly because FWS found that it would threaten a species or damage its habitat. Li also found that the median amount of time it took for the agency to complete an informal consultation was just 13 days (62 days for formal consultations).

The analysis shows that the act “hasn’t been killing the economy, hasn’t stopped jobs,” Li says. “The empirical evidence and analysis shows us that what some people thought was true is not.”

“I’m just floored,” Schwartz says of the new analysis. “I think this is the greatest thing that’s happened with a publication on the [ESA] in several years.”

The paper may or may not alleviate the tension between FWS and Congress, but it will at least help the public see the locations of proposed projects, such as North Dakota, where oil and gas development is now a booming industry. Defenders of Wildlife is publishing an interactive tool that allows anyone to investigate the consultation data and see what species are most affected by projects in a specific state, for example.

The study also raises an important question: Does the decrease in consultations and jeopardy findings mean Section 7 is less effective than it used to be? Or does it just mean that agencies are getting better at complying with the act? FWS’s Gary Frazer believes it’s the latter: “It’s part of the process of learning and having experience in conserving threatened and endangered species,” he says. Still, it’s a question Li is investigating.

Li also plans to use the data he collected to examine whether Section 7 is fulfilling its purpose of conserving species. For example, his team can compare proposals with satellite images to document the total amount of habitat affected by projects in the area. “Data on its own is pretty useless,” he says, “until you put a story with it.”