(Bloomberg Business) — Part of America's advantage over other economies historically has been the pace at which it both creates and destroys jobs. As they face slowing prospects or failure, companies, even whole industries, cut workers . The good news is that new businesses keep popping up to supply new jobs.

More than 7 million jobs are created, and almost as many are destroyed, every quarter in the U.S., according to Maximiliano A. Dvorkin, an economist at the Federal Reserve Bank of St. Louis. That's healthy because "resources are allocated to alternative — presumably better — uses," he wrote in a March 27 blog post.

Except the pace of that churn is slowing.