The labor shift from farming to mining has been linked to food shortages and insecurity. Yet the DRC has some of the richest soils and favorable climatic conditions for food production on the African continent. Before Mobutu's reign, the DRC was one of the major exporters of food to the rest of Africa. "The richly fertile soil (especially that in the eastern highlands which is volcanic in origin) could produce enough food to feed half of Africa, but the country is so poor that at present its people do not produce enough food to feed themselves". As reported by the BBC in 2017, according to Global Witness, more than 20% of the DRC's mining revenue is being lost "due to corruption and mismanagement"; more than $750 million went missing since 2014.