On behalf of the International Comparison Program (ICP) Executive Board and the World Bank, I’d like to thank everyone who’s contributed to the success of the 2011 round. The results are now available in report form , as a data download , and through interactive applications .
The largest global statistical program
The ICP  is hosted by the World Bank, and estimates purchasing power parities, or PPPs, for use as currency converters to compare the size and price levels of economies around the world. In terms of geographic scope, implementation time frame and institutional partnerships, many people consider it to be the largest ever global statistical initiative. It’s conducted under the authority of the United Nations Statistical Commission , and the 2011 ICP round collected over 7 million prices from 199 economies in eight regions, with the help of 15 regional and international partners. It’s the most extensive effort to measure PPPs ever undertaken.
ICP 2011 is a huge achievement, and recognition is due to everyone involved - from the teams who collected prices on the ground in every participating country, to the ICP Executive Board  itself, which provided oversight of the program. And particular thanks are due to the ICP Technical Advisory Group , who provided the invaluable theoretical, conceptual, and methodological advice that has underpinned the ICP’s success.
International cooperation and methodological improvements
Thanks to the relentless efforts of all those participating in this federated governance structure, the work on the ICP has been carried out in a timely manner since its inception in late 2009. This is testament to the effectiveness of a system that’s coordinated statistical operations at national, regional and international levels. This round has seen some significant improvements in methodology; for example, parallel, independent processes were established to validate raw data, compute the PPPs themselves, and review the final results. The ICP 2011 results represent the most comprehensive set of PPPs (and resulting GDP expenditure values) ever produced, using the best methods that have ever been developed.
All major theoretical concepts, methodologies, and computational processes have been consolidated into the book: “Measuring the Real Size of the World Economy” . And it should of course be noted that like all statistical estimates, the PPPs have limitations; but I am pleased to say that these have been explicitly described in the summary report. 
Informing policy with better data
I hope that the ICP 2011 results will find many uses, and that they will help form the basis for research in comparative analysis and policy making. And it is my hope that future global data collection and compilation exercises will be held on a more frequent basis.
My sincere thanks to all those involved in this tremendous global effort. 
The ICP 2011 Summary Results press release can be found here  (Spanish , French , Chinese , Russian , Arabic , Japanese ).