During the early years of its existence, the National Bureau of Economic Research (NBER) assembled an extensive data set on all aspects of the pre-WWII macroeconomy. Until 1978, this data set existed only on the handwritten sheets to which the early NBER researchers copied the data from original...

We describe the theory and practice of real GDP comparisons across countries and over time. Effective with version 8, the Penn World Table (PWT) will be taken over by the University of California, Davis and the University of Groningen, with continued input from Alan Heston at the University of...