Researchers and economists are starting to take a closer look at Africa’s statistics, which they say are often wrong and misleading. A World Bank official goes so far as describing the situation as a statistical “tragedy”.

The headline speaker at a recent conference in Washington called “Poor Numbers! What do we know about income and growth in sub-Saharan Africa?” was Morten Jerven.

His answer: many of the numbers which are circulated in official documents, outside assessments and the media are wrong.

Jerven, a professor at Simon Fraser University in Canada explains why he has made it his academic pursuit to uncover the shortcomings of Africa’s statistics.

“Many economic activities are unrecorded. Thus the numbers, the statistics we produce and which are reproduced through the United Nations, the World Bank and so forth is not really fact, but rather guesses, best guesses with a considerable margin of error attached to them. Sometimes we make decisions using this data without knowing exactly how certain we should be of the evidence we are using," he said.

With much of its economies informal, many African countries have richer citizens than statistics indicate.

This year, Ghana was reclassified as a middle income country, rather than a poor country, after it was found the government and international agencies had for years underestimated average Ghanaian income by over 60 percent. This also means Ghana no longer qualifies for certain World Bank loans.

The World Bank’s chief economist for Africa Shanta Devarajan calls it a statistical tragedy. He says a lot has been done to help African countries, without really knowing the actual effect since the numbers have not been accurate.

“The tragedy here is that we all were happily publishing estimates of Ghana’s growth domestic product for the last 20 years including extolling how Ghana was growing so rapidly and Ghana was actually reducing poverty at a very rapid clip and how well it has been doing and we were taking quite a lot of credit too if I might add," he said.

Work is currently underway to revise Kenya’s average national income upward as well.

Devarajan says in many African countries statistical methodologies will often change from one survey to the next, making comparisons extremely unreliable. He says statistics from many countries are also out of date, or are based on old collection methods.

Angola, Guinea-Bissau and the Central African Republic are some of the African countries where statistics are particularly outdated.

Devarajan says politicians favor ignorance or doctoring statistics rather than having accurate ones, as a tool to remain in power. “They can turn around the statistical tragedy if we recognize the problem as political, we can attack it at its roots. The first is we should insist that all data be accessible and open and transparent," he said.

Devarajan also puts the blame on donors, and the World Bank itself. He says outsiders often rush to get statistics to publish their own reports, and do little to help strengthen a country’s statistical capacity.

Jerven, who is working on a new book on the topic, says it still is a very lonely field among economists, who mostly prefer to use statistics rather than assess their quality. “If you say to an economist that the data quality is poor, you are most likely to meet a shrug of shoulders," he said.

But Jerven says inaccurate statistics are being used to rate countries in all sorts of rankings, and to set new development targets. He says the more grey areas there are in terms of the numbers the more likelihood there is in terms of corruption as well.