Shares of First Interstate BancSystem (FIBK) are experiencing a pre-market plunge of 6.44% on Wednesday, following the release of the company's first-quarter earnings report that fell short of analyst expectations. The significant drop extends the after-hours decline of 5.3% observed on Tuesday, reflecting investors' disappointment with the bank's financial performance.

First Interstate BancSystem reported earnings of $0.49 per diluted share for the first quarter, down from $0.57 in the same period last year. This figure missed the consensus estimate of $0.56 per share projected by analysts polled by FactSet. The earnings shortfall has likely contributed to the sharp decline in the company's stock price.

While the bank's revenue, expressed as the sum of net interest income and non-interest income, showed a slight improvement to $247 million from $242.2 million a year earlier, it still fell short of analyst expectations. The market had anticipated revenue of $253.9 million for the quarter ended March 31, according to FactSet. The combination of lower-than-expected earnings and revenue appears to have shaken investor confidence, leading to the significant pre-market sell-off.