Zions Bancorp’s stock fell Thursday as it added to the noise around bad credit deals on Wall Street by disclosing a $50 million loss on two commercial loans, in what one analyst described as a “step on a rake.”

Zions Bancorp’s stock

ZION was losing 7.2% Thursday, just days after JPMorgan Chase & Co. JPM Chief Executive Jamie Dimon raised concerns about credit-market conditions by noting that “when you see one cockroach, there are probably more,” after his bank took losses on loans made to the now-bankrupt subprime auto lender Tricolor.