Penn World Table

There are three sites that support the Penn World Tables (PWT):

Effective with Version 8, the construction of the Penn World Table will occur at the University of California, Davis and the University of Groningen, The Netherlands.  Documentation and data are available at:

PWT Version 8.0
University of Groningen

Version 7.3 of the Penn World Table is available at: 

PWT Version 7.3
University of Pennsylvania

Version 6.3 of the Penn World Table is available at:

PWT Version 6.3
University of Toronto

References

Robert C. Feenstra, Robert Inklaar. Marcel Timmer (2013). “The Next Generation of the Penn World Table,”
NBER Working Paper no. 19255

Heston, Alan and Summers, Robert. (1996). International price and quantity comparisons: potentials and pitfalls. American Economic Review, 86(2), May. 

Nuxoll, Daniel A. (1994). Differences in relative prices and international differences in growth rates. American Economic Review, 84, December, 1423-36. 

Summers, Robert and Heston, Alan. (1988). A new set of international comparisons of real product and price levels estimates for 130 countries, 1950-1985, Review of Income and Wealth, 34(1), March, 1-25. 

Summers, Robert and Heston, Alan. (1991). The Penn World Table (Mark 5): an expanded set of international comparisons, 1950-1988, Quarterly Journal of Economics, 106(2), May, 327-68.