It’s been a brutal month for traders shorting the riskiest US stocks, and as animal spirits imbue retail investors with boundless confidence, strategists expect the misery to continue for bears.

As of Thursday, investors had lost $2.5 billion in July betting against the 50 US-listed stocks with the highest short interest, according to data from S3 Partners. Doubting the hype in those firms, which include meme-stock darling Kohl’s Corp., produced four times greater losses than the average short in the US market as individual traders have pushed into a number of speculative names.