Optimism among small-business owners edged down in October as firms faced inventory shortages and hiring difficulties forcing them to raise compensation at a historically high rate, according to the National Federation of Independent Business (NFIB). The NFIB’s small-business optimism index fell by 0.9 of a percentage point to 98.2 in October, according to the group’s Nov.9 Small Business Economic Trends report (pdf). The downtick in overall optimism came alongside a sharper four-point drop in the six-month-ahead outlook for business conditions to a reading of negative 37 percent. “Owners have grown pessimistic about future economic conditions as this indicator has declined 17 points over the past three months to its lowest reading since November 2012,” the report reads. The NFIB report showed that 49 percent of small business owners in October reported job openings that could not be filled, a two percentage point improvement from September’s reading, which represented a 48-year record high …