*  *  *  One of the most important economic developments in the United States in the past decade or so has been a sustained increase in the growth rate of labor productivity, or output per hour of work.
This is puzzling at best, but it could mean that Brexit was merely a catalyst for a more general re-evaluation by markets of the amount of short-term government bonds available to investors, possibly related to expectations of central bank purchases or in anticipation of perceived political risks, such as the US election, which was just a few months away.