Will the Fed's Janet Yellen take away Donald Trump's punch bowl?

After three years of almost single-handedly juicing up the slow-growing economy, Janet L. Yellen and the Federal Reserve should be looking at easier days ahead. Yellen, in what will probably be her last full year as Fed chair, may finally get help from somewhere else in Washington. Tax cuts and infrastructure spending planned by President-elect Donald Trump, if backed by the Republican-controlled Congress, would lighten the load for a Fed whose easy-money policies have been the primary economic support for the nation. She is already breathing easier on the Fed's employment mandate; the jobless rate has fallen to a nine-year low of 4.6%. Inflation, too, is under control and, by all accounts, creeping toward the central bank's optimal level of 2%.