Forbes tweaked its formula a bit this year featuring just African billionaires living in Africa rather than the 50 richest people on the continent.

There are 21 billionaires on this year's list and they are worth a combined $70 billion.

Nigerian tycoon Aliko Dangote retains the top spot as Africa's richest man for the sixth year running with an estimated net worth of $12.1 billion.

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Dangote is joined by only two other Nigerians on the list - telecom tycoon Mike Adenuga, who is ranked as Africa's third richest person with an estimated $5.8 billion fortune, and oil magnate Folorunso Alakija who has an estimated $1.6 billion fortune.

Two Nigerians who are regularly featured on past versions of the Forbes list dropped off it this year.

Oil marketer Femi Otedola, whose net worth dropped from $1.6 billion in 2015 to $330 million today, is first while sugar tycoon Abdulsamad Rabiu, whose net worth dropped below the $1 billion mark thanks to an extremely weakened Naira, is the second.