Republicans sold the 2017 tax law as “rocket fuel” for American  investment and growth, saying that corporations — flush with cash from  lower tax rates — would channel money back into the economy by building  factories and offices and investing in equipment, which would help companies grow and provide winnings for workers. But, so far, hard evidence of such an acceleration has yet to appear in economic data, which show more of a steady investment roll than a rapid escalation.

President Trump promised that his tax cut would encourage companies to invest in factories, workers and wages, setting off a spending spree that would reinvigorate the American economy. Companies  have announced plans for some of those investments. But so far, companies are using much of the money for something with a more narrow  benefit: buying their own shares.