EIGHT-THIRTY in the morning on the first Friday of every month is a special time for bond traders: it’s when America’s Bureau of Labour Statistics usually releases its monthly jobs data. Despite the vast sums that some hedge funds spend on alternative data, landmark releases like the employment report or the consumer-price index (CPI) can still convulse markets. When the September payrolls numbers, released on October 4th, blew past expectations, bond yields jumped by eight basis points (0.08 percentage points). Stocks spiked, too, though the move was short-lived.