Groundnuts: “In 1968 Nigeria was the world biggest producer of groundnuts (averaging 712,600 tonnes a year)” Columbite: “...and the biggest producer of columbite.” Palm oil: “...seventy per cent of the world’s export of palm oil” – Nigeria supplied most of the exports, but this does not necessarily mean it was the biggest producer. Rubber: Nigeria produced rubber, but there's no indication it was the biggest producer. Cocoa: “the second producer of cocoa ... after Ghana” Palm kernels: “supplied half the world’s export of palm kernels” – again, export doesn’t mean production. ❌