Facing growing criticism from Wall Street, Federal Reserve Chair Janet Yellen earned her worst grade yet in the latest CNBC Fed Survey.

The 41 survey respondents, who included money managers, investment strategists and economists, gave Yellen a C+ overall grade — a full letter markdown from the last time she was graded, six months ago.

Only 8 percent granted the Fed chief an “A” rating, down from 36 percent in April.

“She appears indecisive, even if she knows what she wants to do,” said Joel Naroff, president of Naroff Economic Advisors.