In 2010 I calculated (for a Christian Aid report) that if Zambia had received in 2008 the same export prices in each copper category as had been declared on Swiss exports, then Zambia’s recorded GDP would have been 80 percent bigger. In a subsequent CGD working paper with Petr Janský and Alex Prats, my co-authors and I broadened this analysis to more countries and commodities, and introduce an ‘excess margin’ methodology to compare Swiss pricing patterns with those of other trading countries.
Last week Maya Forstater published a critique of these calculations. I agree with much of this, and so we are going to redo our analysis.
Excellent piece of digging by Maya there. And fair play to CGD for putting their hands up and conceding.
If only some other people would similarly admit to error.
Now the next step is to go back and scrub those reports that relied upon that earlier, incorrect, analysis….