A salutary reminder that just because things are measured precisely (such as money) doesn’t mean that the measurements are valid or useful. As reported by Louise Story, Landon Thomas Jr and Nelson D. Schwartz, in the New York Times on 13 Feb 2010 :

As in the American subprime crisis and the implosion of the American International Group, financial derivatives played a role in the run-up of Greek debt. Instruments developed by Goldman Sachs, JPMorgan Chase and a wide range of other banks enabled politicians to mask additional borrowing in Greece, Italy and possibly elsewhere.

In dozens of deals across the Continent, banks provided cash upfront in return for government payments in the future, with those liabilities then left off the books. Greece, for example, traded away the rights to airport fees and lottery proceeds in years to come.

Critics say that such deals, because they are not recorded as loans, mislead investors and regulators about the depth of a country’s liabilities.