Xavier Sala-i-Martin and Maxim Pinkovskiy write,

The poverty rate in 1970 was 0.398. That is, close to 40% of the entire population lived with less than one dollar a day in Africa in 1970. After a small decline during the first half of the seventies, the rate jumped to around 0.42 in 1985 and stayed more or less at that level for a decade. In 1995 there is a dramatic change in trend: the poverty rate began a decline that led to a ten percentage point reduction by 2006…

These results contradict the 2008 Millennium Development Goals Report (UN, 2008), which asserts that “little progress was made in reducing extreme poverty in sub-Saharan Africa.” Our estimates disagree: the African poverty rate in 2006 was 0.318, 30% lower than in 1995 (0.428) and 28% lower than in 1990 (0.421).

Can anyone find an ungated copy of the paper to which I could link? [UPDATE: Tyler found one here.]