American stocks are at their most expensive in decades

Try a little, and it is never too hard to argue that the stockmarket looks risky and a crash must be coming. But in the long run such arguments are usually best ignored. Since 1900 American shares have posted an average real return of 6.4% a year. Over three decades, that would transform the purchasing power of $1,000 into $6,400. Bonds, the main alternative, do not come close. With an average historical return of 1.7% a year, they would generate a measly $1,700. Cash would do worse still.