The proportion of consumers surveyed by the central bank who reported receiving three or more job offers this summer is the biggest since records began in 2014. Of those polled by the New York Federal Reserve Bank in July, 2.8% reported the multiple job offers, while almost 16% received one or two offers of employment — also a relatively high proportion. The data point to the historic tightness in the labor market, even as the longest U.S. economic expansion on record shows signs of flagging.