That fatal slide occurred in the first half of the decade at American Business Financial Services Inc., a subprime-mortgage lender in Philadelphia that went bust in 2005 with losses of $700 million for thousands of mostly elderly mom-and-pop investors.
“If forced to choose one phrase to describe the U.S. economy in the 21st century's first decade, ‘Ponzi scheme’ would not be bad,” posed professor Frankel.
The bubble in real estate values that defined the period was not a Ponzi scheme in the traditional sense, but it still depended on taking money from one party to pay another.
As long as house prices rose, borrowers could refinance their mortgages, paying off the old lender with money from a new one. When the new money dried up, the entire country crashed and nearly brought the world economy down with it.
It happened with Philadelphia's own Ponzi schemers: Joseph S. Forte on the Main Line, Ron Schnable in the Mennonite stronghold of Souderton, and allegedly with Tony Young in Chester County horse country, and maybe with Troy Wragg of Manayunk, who has denied civil charges.
Solid data on Ponzi schemes, which are not legally defined, are hard to get, experts said. A spokesman for the Securities and Exchange Commission (SEC) said the agency filed charges in 70 of the schemes in 2007 and 2008. In 2009, there were 55 as of Dec. 4.
Counting Ponzi artists may be hard, but once they are exposed, it is easy to see they have a lot in common.
They tend to be entrepreneurial hustlers, and they gain credibility by winning over a pillar of the community or by exploiting a connection to a group. Like gambling addicts, they are always looking for one last chance, Frankel said. Forte, for example, told his probation officer that the only way he could reimburse his victims was to have another shot at investing.
Some Ponzi artists are crooks from the start, said criminologist Adam Graycar, who recently left Rutgers University in Newark. Others start with good intentions, he said, but resort to what are supposed to be stopgap measures, and then go too far to turn back.
Among the victims are the greedy and the trusting. "When you've got the greed and the crook together, then you've got dynamite," Graycar said.
Ron Schnable: Predator
Ron Schnable remained relatively obscure while operating a series of schemes from 1995 to 2003 that took advantage of middle-class Montgomery County Mennonites and others around Souderton.
When Schnable appeared for sentencing last January in federal court in Philadelphia, wearing a green prison jumpsuit, his face covered by a bushy beard and his scraggly hair pushed across his balding head, it was hard to imagine him as a man able to persuade his victims to mortgage their homes and give him that money.
Joseph S. Forte: Classic scheme
Joseph S. Forte, finding his victims on the Main Line, operated in a much different milieu than Schnable, but the two shared a drive to establish themselves as businessmen.
Before starting an investment fund in 1995 that over 13 years defrauded 76 investors of $35 million, Forte owned a gym in Havertown and then a computer-sales business in Upper Darby.
In some ways, Forte, 53, was a textbook Ponzi schemer. He got his start by winning over leaders of the community, including a Main Line accountant he became friendly with at meetings of the Haverford Township Rotary Club.
Tony Young: High-living
The approach of Chester County's Tony Young, who has been accused by the SEC of a $23 million investment fraud, differed markedly from that of Forte.
Like Forte, Young, 38, gained access to investors through connections with well-respected members of a community. In the place of Forte's Main Line businessmen and Schnable's Montgomery County Mennonites, Young found wells of cash on Chester County horse farms.
Troy Wragg: Odd math
It takes a strong salesman to pull off a Ponzi scheme.
Troy Wragg, who is fighting civil charges by the SEC that he operated a Ponzi scheme with a hook in green technology, has a compelling personal sales pitch down pat.
He spoke of a stable childhood in Allentown - just before mentioning that he had been homeless as a boy. Then Wragg talked of starting a cleaning business at the age of 17, specifying that it happened about four years after his bout with homelessness.
That math might not work out, but some of the 100 investors who gave $54 million to Wragg and his Mantria Corp. of Bala Cynwyd since 2007 remain convinced that the math behind guaranteed annual returns of at least 17 percent was sound.