CHICAGO—Producers of the long-running Chicago Public Radio program This American Life announced Monday that they have completed their comprehensive 12-year survey of life as a modern upper-middle-class American.

Ira Glass compares completing the series to finding out he is a relative of composer Philip Glass.

In what cultural anthropologists are calling a "colossal achievement" in the study of white-collar professionals, the popular radio show has successfully isolated all 7,442 known characteristics of college graduates who earn between $62,500 and $125,000 per year and feel strongly that something should be done about global warming.

"We've done it," said senior producer Julie Snyder, who was personally interviewed for a 2003 This American Life episode, "Going Eclectic," in which she described what it's like to be a bilingual member of the ACLU trained in kite-making by a Japanese stepfather. "There is not a single existential crisis or self-congratulatory epiphany that has been or could be experienced by a left-leaning agnostic that we have not exhaustively documented and grouped by theme."

Added Snyder, "We here at public radio couldn't be more pleased with ourselves."

The final episode, which explored the universal tribulations of having to live with roommates again in one's mid-30s after a divorce, provided an apt bookend for the project. The completed work is expected to be an indispensable source of information for years to come about the thoughts and tastes of bespectacled cynics prone to neuroses who are actually doing just fine.

This American Life host and producer Ira Glass began work on the project in 1995 in Chicago, where he found himself inspired by and catering to an audience of professionals who dine out frequently and have a hard time getting angry. Glass and his team of producers, writers, and interns set about the exhausting task of gathering all available information on a range of subjects from minor skirmishes with the law to the rewards of occasionally talking to poor people. The raw data was then analyzed, deconstructed, reconstructed, re-deconstructed, organized under a broad philosophical title, and interspliced with musical interludes by rock duo They Might Be Giants.

Though This American Life is now lauded as the definitive source for material about getting an autistic teenager admitted to Harvard, its early run was marked by painful trial-and-error, according to producer Alex Blumberg.

"At first, we were getting a lot of stories from recovered drug addicts and East African refugees living in the States, which had their compelling elements but came off a bit cloying," Blumberg said. "But then we realized that if we had overeducated people with voices rather unsuitable for radio narrate the stories with clever analogies and accessible morals, the whole thing would come off far less depressing."

Blumberg said that the turning point came in 1997, when producers discovered a group of inner-city schoolchildren inadvertently teaching an important lesson to their attractive, suburban-raised teacher about what makes us human.

Also aiding the study were the many contributors to This American Life, who took time from their best-selling essay-writing careers to donate personal anecdotes about dropping out of prestigious art schools, taking harrowing but poignant childhood vacations to the Grand Canyon, and the unique challenges of growing up in families supportive of their homosexuality.

On Sunday, writer and contributing editor Sarah Vowell called the project's end "oddly anticlimactic," but questioned whether work was actually complete because the show had not yet addressed the subject of "Things Ending."

"Seeing this project through to its culmination was equally satisfying and strange," said Vowell, speaking at a book signing in Colonial Williamsburg dressed as Betsy Ross. "I feel not unlike the early Pilgrims, who, standing atop Plymouth Rock after a long and arduous sea voyage, reflected on their journey, perhaps thinking to themselves 'For God's sake—doesn't anybody have anything to eat in this settlement?'"

Glass, who personally contributed over 2,000 anecdotes from his own life for documentation, called the project's conclusion the "end of an era."

"When we finished, I have to tell you, I felt something I never expected: a profound sense of contentment—maybe even relief," Glass said. "Afterwards, the other producers and I sat around for a long while, remarking on how interesting and strange it was to finally complete the study, and how perhaps it is, in some way, symbolic of life in general."