Sharecast - CMC warned last month that annual net operating income would be lower than last year as revenues continued to fall in a "challenging" environment.
It said subdued market conditions had continued through August, with trading and investing net revenues trending 20% lower year-on-year.
RBC (TSX:RY) said it was cutting its net operating income by 18% on average across its forecast period following the recent unscheduled trading update.
"The drop-off in volatility seen year-to-date has been untimely for CMC (LON:CMCX) as it has coincided with a period of elevated cost owing to investment in strategic initiatives," it said. "The operating de-leverage effect means earnings per share estimates fall by 70% on average.
"We look to 1H results in November for an update on medium-term targets, but in the interim we see valuation support from the high proportion of market cap now covered by surplus own-funds, and retain our outperform, speculative risk rating."