The investment grade rated bond eventually sold at a slight discount from par and fetched a yield of 4.5%, over 250 basis points over 10 year U.S. Treasury bonds.

FORBES: Investors Get 4.5% Yield On Brazil's Vale Bonds

It resulted in a slight fall in the number of pupils achieving at least a C-grade, from 65.4% to 63.9% this summer.

BBC: GCSE English: How is it marked?