i. Central statistical agencies ii. Historical reconstructions iii. Estimates iv. Conjectures Virtually all benchmark data after 1960 (i.e. 1960, 1970, 1980, 1990, 2000, and 2010) are derived indirectly from Central Statistical Agencies and therefore probably better classify as historical reconstructions. The remaining data are estimates

General references

The main sources, with the exception of some country-specific studies, are:

* Mitchell, B.R. (2007), International Historical Statistics: Africa, Asia & Oceania, 1750-2005, Basingstroke [etc.]: Palgrave Macmillan (5th edition).

* Mitchell, B.R. (2007), International Historical Statistics: The Americas, 1750-2005, Basingstroke [etc.]: Palgrave Macmillan (5th edition).

* Mitchell, B.R. (2007), International Historical Statistics: Europe, 1750-2005, Basingstroke [etc.]: Palgrave Macmillan (5th edition).

* US Department of Commerce, US Census Bureau, International database, downloaded from: http://www.census.gov/population/international/data/idb/informationGateway.php

* Unesco, Statistical yearbook, Paris: Unesco, 1964-1999, 1963-1999

* Blue books of the British colonies (various issues)

Some of the data are also taken from papers:

* Péter Földvári and Bas van Leeuwen, 'Educational inequality in Europe, 1870-2000 ,' 20 August 2010.

* Leeuwen, Bas van, Jieli van Leeuwen-Li, and Péter Földvári, 'Regional human capital in Republican and New China: Its spread, quality and effects on economic growth,' 26 July 2011.

* Leeuwen, Bas van, Jieli van Leeuwen-Li, and Péter Földvári, 'Was education a driver of economic development in Africa? Inequality and income in the twentieth century,' 23 April 2012.

* Didenko, Dmitry, Peter Foldvari, and Bas van Leeuwen, `A dataset on human capital in the former Soviet Union area: Sources, methods, and first results,' CGEH Working Paper No. 35, Aug. 2012.

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