There's a German book called "Preußen und die Marktwirtschaft" ("Prussia and Capitalism") by Ehrhardt Bödecker. (<a href="http://www.amazon.de/Preußen-die-Marktwirtschaft-Ehrhardt-Bödecker/dp/3789281875" rel="nofollow">http://www.amazon.de/Preußen-die-Marktwirtschaft-Ehrhardt-Bö...</a>)<p>It cites a lot of statistics showing how the public sector swelled in the federal republic compared to the Kaiserreich.  (Prussia made up the vast majority of the Reich.)  Alas, it seems to be only available offline and in German.