Nigeria said it lost out on as much as $100 billion in revenue last year as attacks by militants in the oil-rich Niger Delta cut crude output to a record low.( This is huge)
Production fell by 1 million barrels a day to 1.2 million a day at the peak of the attacks, Emmanuel Kachikwu, minister of state for petroleum, said Tuesday in a video-clip on his Facebook page.

E-payment transactions rose to N51.8trn in 2016 – CBN

Last year, Nigeria suffered its first full-year recession since 1991 as a resurgence of armed conflict in the delta, combined with lower oil prices, blighted the economy. ( What kind of silly excuse is this)

While recent peace efforts have curbed the frequency of attacks on oil infrastructure, the West African nation has struggled to boost output as one of its largest export terminals remains closed.

Source http://www.nairausd.com/2017/02/nigeria-loses-up-to-100bn-in-revenue-as.html

Another reason why Buhari's poor leadership caused the recession..He lost 100 billion dollars because he wanted to get Tompolo arrested over some over inflated 13 billion naira contract ..who does that?