Before the data is released I felt it important to get my take on GDP revisions out there. There will be the standard outcries about political manipulation of the numbers and this is really not the intent, nor the outcome, of this process. This article from Bloomberg.com explains the process a bit. This article does a little better (especially on the R&D front and it mentions economic history). The U.S. economy is dynamic and constantly changing. We can call it innovation or entrepreneurship or development, but at its root it is change. Change in the products and services made and changes in the processes used to make them. These changes require us to change how we account for different aspects of the economy over time.