Brazil is expected to announce plans for a potentially massive sovereign wealth fund this week, based on the country’s coming oil wealth. One of the fund’s aims, according to Guido Mantega, finance minister, will be to counter the appreciation of Brazil’s currency, the real, by using the fund to put foreign currency that would otherwise have entered Brazil (pushing up the real) in an offshore account.

While there seems little doubt that Brazil is indeed sitting on enormous oil reserves, the government is engaging in wishful thinking if, as Mr Mantega says, it expects revenues to start flowing within three to five years.