Judging by recently reported indicators of global economic activity, this outlook is now being borne out. The March 2021 data are consistent with an outright boom, especially in manufacturing. The recovery may be stronger than even I had anticipated, and by the end of March, the S&P 500 had risen above 4,000 for the first time. The question, of course, is what will happen next. Will the boom last? To answer that, we should start with the most recent evidence. Among the more eye-catching figures reported for March is the Institute for Supply Management’s Purchasing Managers’ Index (PMI), which rose by 3.9 points from February to reach 64.7. The survey was published on April 1 – assuming it wasn’t a prank, that is the highest level since 1983.