The world looked very different when ProPublica posted its first story five years ago today. Unemployment stood at 5.5 percent. The phrase "Too Big to Fail" had not yet entered the lexicon. And BP had rebranded itself as a company dedicated to green energy.

It was unclear whether a nonprofit, investigative newsroom could find an audience on an Internet that flocked to stories about breaking news and celebrities. ProPublica's plan to collaborate with major news organizations raised eyebrows; no one knew whether reputable publications would work with outsiders on potentially controversial subjects.

Today, thousands of stories later, those concerns seem quaint. Readers turned out to be hungry for substantive, well-documented reporting. ProPublica's first major story appeared on CBS' "60 Minutes" and was followed by partnerships with The New York Times, Los Angeles Times, USA Today, Politico, The Washington Post, PBS' Frontline, NPR, The Atlantic, The New Yorker and Time, among many others. More nonprofit news organizations focused on investigative reporting sprang up across the nation and around the world. This year, a Chinese journalist who faced pressure from the government quit his job, declaring that he wanted to create something like ProPublica.

ProPublica was founded by Paul Steiger, the former managing editor of The Wall Street Journal (and now our executive chairman). It was primarily funded by Herb and Marion Sandler, philanthropists who recognized the effect that newspapers' economic troubles were having on our democracy. Their generosity in those early years made it possible for the organization to find its voice and develop expertise in health care, the environment and Wall Street. We moved to assemble and make available to the public vast databases on pharmaceutical companies' payments to doctors, the government's stimulus programs, the quality of dialysis care and, most recently, doctors' prescribing habits in the Medicare program. These efforts have given readers and other journalists throughout the country the chance to explore and analyze data that changes lives.

As an organization that was born on the Internet, we have tried to take full advantage of the conversation with and among readers made possible by the new technologies. Our readers play a crucial role in our journalism, helping us to investigate everything from campaign finance to patients harmed by medical procedures. We are grateful to all who have contributed ideas and time to our work.

More recently, ProPublica has worked to create a more diverse funding model, seeking earned income and raising money from thousands of individual donors as well as family and institutional foundations. We expect that more than two-thirds of our revenue in 2013 will come from sources other than the Sandler Foundation.

We have no doubt the next five years will bring new challenges. More people will get their news from mobile devices and tablets. New kinds of websites will be developed and proliferate. The business of journalism will evolve unpredictably. But one aspect of national life will remain constant — as it has for centuries. Governments, businesses and powerful individuals will occasionally abuse their powers and betray the public trust. And reporters from ProPublica will be trying to expose them. Thanks for your support of this work, for reading, for getting involved, and for being part of our community.

See also:For 5th Anniversary, ProPublica Looks Back at Lives Changed