Pieter (Jop) WOLTJER

Researcher – Wageningen Economic Research



Article: Is Egypt Really More Productive than the United States?

The Data behind the Penn World Table

ABSTRACT: A new feature in recent versions of the Penn World Table (PWT) is data on comparative levels of total factor productivity (TFP) across countries. TFP is defined as the efficiency with which inputs are transformed into outputs, and differences across countries can be due to factors such as better technology or better resource allocation. Yet, surprisingly, in PWT version 10.0, a number of low-income countries have a TFP level well above that of the United States. Continue reading “Article: Is Egypt Really More Productive than the United States?”

Working Paper: Inconsistencies in Comparing Relative Prices Over Time

Patterns and Facts

ABSTRACT: Purchasing power parities (PPPs) aim to measure relative price levels across countries, like inflation aims to measure relative price levels over time. Ideally, the change in PPPs over time should be consistent with relative inflation, Continue reading “Working Paper: Inconsistencies in Comparing Relative Prices Over Time”

Column: An Economic Rationale for the West African Scramble?

The Commercial Transition and the Commodity Price Boom of 1835–1885

This paper uses a new trade dataset showing that sub-Saharan Africa experienced a terms of trade boom in the five decades (1835–1885) preceding the European “scramble for Africa” which was comparable to similar export booms in other parts  Continue reading “Column: An Economic Rationale for the West African Scramble?”

Dataset: African Commodity Trade Database

The African Commodity Trade Database (ACTD) aims to stimulate and deepen research on African and global economic history. The database provides export and import series at product level for more than two and a half centuries of African trade (1737-2010). Continue reading “Dataset: African Commodity Trade Database”

Working Paper: Commodities, Prices and Risk

The Changing Markets for Non-slave Products in Pre-abolition West Africa

ABSTRACT: Using a newly constructed dataset on the quantities and prices of African commodities over the long 18th century this paper provides new insights into the changing nature of the non-slave trade with West Africa in the era before the abolition Continue reading “Working Paper: Commodities, Prices and Risk”

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