Top economist David Rosenberg said the Fed should put bigger rate hikes back on the table after bouts of 'speculative lunacy'

• The Federal Reserve should weigh up another big interest-rate increase because of recent "speculative lunacy", according to David Rosenberg.
• "I am starting to wonder if 50 basis points shouldn't be back on the table," the top economist said.
• Most traders expect a 25-basis-point hike Wednesday.

The Federal Reserve should consider bringing in a bigger-than-expected rate hike Wednesday to crush a recent bout of speculation in markets, according to top economist David Rosenberg.