The scope of the problem
The Tax Justice Network (TJN), a coalition of campaigners opposed to tax havens, put the amount of personal wealth held offshore at $11.5 trillion – more than four times the total US national budget for 2007. The OECD posits a more conservative figure: $5 trillion to $7 trillion.
In total, TJN estimates that the world's exchequers are deprived of at least $250 billion a year. Britain reckons its annual income-tax shortfall is $40 billion, Germany $30 billion, and the US as much as $100 billion a year.
"Tax havens have declared war on honest taxpayers," says US Sen. Carl Levin (D) of Michigan, who along with Sen. Barack Obama (D) of Illinois is co-sponsoring the "Stop the Tax Haven Act," introduced last year. "What this [German scandal] demonstrates again is that tax-haven abuses are a worldwide problem."
It may also have unsettled some tax dodgers. Mr. Zumwinkel was the most high-profile of more than 160 suspects to be netted, and more than 150 have voluntarily come forward. Since then, dozens of Dutch nationals have also volunteered information about their savings. And there could be more: Last week, German newspaper Die Welt reported that a former employee of a Swiss bank offered to sell German officials files listing more than 30,000 account holders.