'This is a book of unusual originality and sophistication. In the burgeoning literature of history of statistics, it is one of the first and unmistakably the best to focus on the production and use of economic numbers … He provides wonderful insights into the circumstances of the German economy during this traumatic era. In short, he makes the history of economics and of statistics speak to central questions of the historical development of state and economy in Germany … a work of impressive historical scholarship, a skilful disinterment of issues from a much-worked historical field … This is a superb book, which deserves to be issued in paperback so it can be widely read.' Ted Porter, Journal of Economic History

'This important and interesting book will be of great value not only to discussions of German political economy in the first half of the twentieth century but also to debates about economic knowledge and how it develops … extraordinarily ambitious … compelling reading.' Harold James, Business History Review

'… an original and important book ... a very readable book, stimulating, indeed exciting to the very end.' Knut Borchardt, Historische Zeitschrift