Senior level CPAs have turned much more pessimistic about the economy. And somewhat surprisingly, they are partly concerned about deflation.

Just 21 percent of CPAs serving as C-suite executives said they are optimistic about the US economy, way down from 40 percent who were optimistic in May and the lowest level since April 2009, according to the American Institute of Certified Public Accountants and the University of North Carolina's Kenan-Flagler Business School's latest Quarterly Economic Outlook Survey. What's more, pessimists outnumbered optimists by a two-to-one margin.