Africa’s richest man Aliko Dangote, has seen a significant drop in his net worth in the last year, despite the launch of the Dangote refinery. The year leading up to July 29th, saw the Nigerian businessman and philanthropist lose over $1 billion. Aliko Dangote’s net worth dropped over $1 billion in the last year.Dangote’s current net worth is estimated at $13.8 billion by Bloomberg and $12.4 billion by Forbes.The launch of Dangote’s oil refinery was expected to increase his revenue, but it has faced complexities.Bloomberg’s billionaire index has Dangote’s current net net worth at $13.8 billion…