(Bloomberg) -- CMC Markets Plc slumped the most since 2016 after warning of a slowdown in activity as the pandemic-fueled retail trading boom eases. 

“Reduced volatility in markets has resulted in lower trading activity across both the newly acquired and existing cohort of clients,” the London-based firm said in an unscheduled update, sending the stock down as much as 29%. 

CMC, a provider of contract-for-difference products that allow traders to speculate on price movements without owning the underlying securities, was one of a raft of companies that benefited from people stuck at home during the pandemic being enticed to markets by a spike in volatility. The so-called “meme-stock” craze in early 2021 further aided business. 

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“Market activity has remained subdued through July and August following on from the moderation in activity reported” in the first quarter, CMC said Thursday. It added that client retention was tracking below its long-held target of 80%, suggesting some newer customers may have become disinterested as restrictions were lifted. 

CMC now anticipates 2022 net operating income of 250 million pounds ($345 million) to 280 million pounds. That’s 15%-25% lower than prior expectations, Shore Capital’s Vivek Raja wrote in a note to clients. 

Stuart Duncan, an analyst at Peel Hunt, which also acts as CMC’s broker, said the profit warning “is likely to reflect a combination of factors: reduced volatility, fewer reasons to trade, and clients taking holidays as restrictions have eased.” 

CMC was down 28% to 301.5p as of 9:30 a.m. in London, with peers IG Group Holdings Plc and Plus500 Ltd. down 5.2% and 3.1%, respectively.

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