IBM’s stock plummeted on Tuesday in its largest single-day loss in its 115-year history, after CEO Arvind Krishna warned investors the computing firm’s latest quarter was “worse than our expectations” while failing to adapt to rising chip costs.

“What played out was worse than our expectations,” CEO Arvind Krishna warned investors.

Shares of IBM crashed 25.2% to around $217 at market close on Tuesday, topping the infamous Black Monday crash of Oct. 19, 1987, when IBM plummeted 23% amid the broader, massive selloff.

That erased about $67 billion from IBM’s market capitalization, valuing the firm at just under $205 billion.

The historic decline followed a letter from Krishna to IBM investors on Tuesday, in which Krishna said about the company’s “disappointing” second-quarter performance: “What played out was worse than our expectations. We did not adapt and move quickly enough.”