It’s not enough for most people to know what the unemployment rate is and whether it’s going up or down. It’s not enough for investors and entrepreneurs living during some of the strangest times in American financial history. And it’s not enough for citizens trying to decide whether the policy proposals now in Washington are worthy of their support. If you fall into any of these categories, you need to know more about the labor market than the headline numbers. In particular, you need to know the JOLT...