I want to know the answer to the following question:
In 2011 rankings, how bad was Nigeria's corruption ranking?
All the background I'm provided with is that "After the conclusion of the NNPC's account Audit, it was announced in January 2015 that NNPC's non-remitted revenue is actually US$1.48billion, which it needs to refund back to the Government.". Is that enough to answer the question?