The humorous insight into his pre-fame days came as he gave evidence for the second day against his former accountant, Keith Moore, 51, who is accused of stealing pounds 6m from him.
He was being asked questions by Nicholas Purnell QC, for Mr Moore, about statements sent to him by his bank, Coutts. These detailed transactions on one of his accounts, from which the prosecution claims that Mr Moore, Sting's financial adviser, illegally transferred pounds 4.8m to a Bank of Scotland account over which he had sole control.
Southwark Crown Court has been told that Mr Moore, of Fulham, south- west London, who denies 15 sample counts of theft, lost most of the money in a series of speculative ventures. The accountant used more than pounds 1m to stave off bankruptcy twice. Sting said that although he received regular statements from Coutts, long tours abroad meant he was often presented with a bundle of them at once.
He explained he did his best to look through them but was simply "not qualified" to understand them properly.
Mr Purnell said: "They are not in coded terms. You don't need undercover agents, hieroglyphics, to get to them."
Sting agreed, but said his understanding of his highly-complex business affairs was derived from a series of "copious and verbose" letters Mr Moore sent to him. They did not contain any reference to the existence of an account at the Bank of Scotland, of which he said he remained in ignorance until Mr Moore's alleged thefts came to light.
Mr Purnell said the singer was "not an innocent abroad ... you took an A-level in economics. I am not suggesting that opens the gates of the financial world. You also had an unhappy period working for the Inland Revenue and you can't have somebody at the Inland Revenue who is horrified by financial documents".
Sting replied: "I am afraid that is really why I was forced to leave the Inland Revenue."
Mr Purnell said Mr Moore secured an agreement with the Inland Revenue that the star should not be taxed on his foreign earnings.
It saved him pounds 4.8m on pounds 11.6m of income between 1986 and 1991. Mr Purnell claimed that, with Sting's knowledge and approval, the money was transferred to accounts controlled by Mr Moore.
"Are you saying that I agreed that all the money saved from the Inland Revenue would go to an account controlled by Mr Moore? ... I don't think I did," Sting said.
Sting revealed that Coutts had reimbursed him for the pounds 4.8m transferred to the Bank of Scotland.
The trial continues on Tuesday.Reuse content