“Annual income twenty pounds, annual expenditure nineteen six, result happiness. Annual income twenty pounds, annual expenditure twenty pound ought and six, result misery.” This is the immutable financial insight told to David Copperfield in Charles Dicken’s eponymous classic. The quote neatly underlines the common sense wisdom to spend less than you earn. And as Adam Smith said, “What is prudence in the conduct of every private family can scarce be folly in that of a great kingdom.”