Controversy, Facts and Assumptions: Lessons from Estimating Long Term Growth in Nigeria, 1900–2007 (SWP 13)

This article contributes to the debates surrounding ‘New African Economic History’ by exploring the feasibility of constructing a time series of economic growth in Nigeria spanning the 20th century. Currently most datasets for African economies only go back to 1960. The sources for their creation exist, but these valuable colonial data remain underutilized. This is a first exploratory paper in a project aiming to create measures of economic growth through the 20th century for a sample of African economies. The paper offers a systematic discussion of the different available datasets on population, agricultural production and income for the country. It finds that the existing data, often presented as facts, are more accurately described as projections based on assumptions. If these assumptions are already made in the production of the data, this precludes empirical testing of important questions. The main lesson is that any African economic history investigation must both begin and end with a critical analysis of the quantitative data, and must further be supported by careful qualitative evaluation.