It will be the standard empirical source on African infrastructure for the foreseeable future. According to the report, the public infrastructure in most African countries increasingly lags behind those of poor countries in other regions -- in part due to Africa's difficult geography, but largely thanks to governments' and private actors' chronic underspending. For instance, in 1970, Africa's per capita power generating capacity was three times as great as South Asia's; now, it is less than half as great. Lagging infrastructure, the report estimates, depresses firms' productivity by about 40 percent. The solution, it suggests, is to more than double infrastructure spending from present levels. Given that total investment in Africa's infrastructure has already doubled over the last decade, this only confirms the depth of the problem.