Elizabeth Trenbeath of Snelling Staffing in Lexington, S.C., holding paper, says she has been overrun with businesses seeking workers. A surge in hiring by American small businesses could run afoul of the Federal Reserve’s efforts to cool inflation . Small companies have been responsible for all of the job growth in the U.S. since the onset of the Covid-19 pandemic and account for almost four out of five available job openings, according to a Wall Street Journal review of labor data and an analysis by Jefferies.