Global Financial Integrity (GFI) estimates that in 2013, US$1.1 trillion left developing countries in illicit financial outflows. Its methodology is considered to be quite conservative, as it does not pick up movements of bulk cash, mispricing of services, or most money laundering.
GFI estimates that about 45 per cent of illicit flows end up in offshore financial centres and 55 per cent in developed countries.
University of California, Berkeley Professor Gabriel Zucman has estimated that 6 to 8 per cent of global wealth is offshore, mostly not reported to tax authorities.
Many tax avoidance schemes are not illegal. But just because it is not illegal does not mean it is not a form of abuse, fraud or corruption. To tackle the corruption at the heart of the global financial system, tax havens need to be shut down, not reformed, the experts say.