Even a small change in the economic assumptions underpinning the surplus projections can make a big difference.

ECONOMIST: Tax-cuts with a purpose

Unlike the goods and services prices index, the GDP deflator measures change In compensation of employees, operating surplus (including mixed income), and consumption of fixed assets arisen from changes in prices and nominal net taxes.

UNESCO: Belarus: Report: Part I: Descriptive Section

The real change came in donor dependency, which measures the share of a nonprofit's surplus coming from contributions as opposed to sale of goods or services or investment performance.

FORBES: Charity Begins With The Boss

Tracy Carty, a climate change policy adviser from Oxfam agrees that the issue of surplus carbon permits could be very important in the negotiations.

BBC: Doha climate talks: Will 'hot air' derail the process?