For the last few years, the Architecture Billings Index has played a very important role in determining the nature of the construction market and in helping the architecture of a region become financially tangible to a larger audience. 

First off, how are the Billings calculated? It sure should involve a great role played by the studios and firms that help put a number to the projects that are being done. But apart from the obvious, how are the numbers realized? 
 

Secondly, and this is more important to me: why hasn't a tool as resourceful as the Billings Index surfaced across multiple countries and continents across the globe? It seems like only the United States has their architecture financial projections figured out. I.M.O., there is a great need for the A.B.I. to be available in multiple countries-either by organizations that help calculate the A.B.I. or by some statutory body that does so. 

Thanks.