Overall optimism among small-business owners edged down in September while the level of confidence in the six-months-ahead outlook for business conditions fell to a nine-year low as inflation and hiring difficulties took a bite out of sentiment, according to the National Federation of Independent Business (NFIB). The NFIB’s so-called optimism index fell by one percentage point to 99.1 in September, according to the group’s Oct. 12 Small Business Economic Trends report (pdf). The downtick in overall optimism came alongside a sharper five-point drop in the six-months-ahead outlook for business conditions. The forward-looking index of future expectations fell to a reading of negative 33 percent, the lowest number since December 2012. “Small business owners are doing their best to meet the needs of customers, but are unable to hire workers or receive the needed supplies and inventories,” NFIB Chief Economist Bill Dunkelberg said in a statement. Hiring woes, supply chain problems, rising …