Shares of Koppers Holdings Inc. (NYSE: KOP) plunged 17.04% in pre-market trading on Friday following the release of disappointing second-quarter results and a downward revision of the company's 2025 outlook. The wood treatment and carbon compounds manufacturer's performance fell short of analyst expectations, raising concerns among investors about its near-term prospects.

Koppers reported adjusted earnings per share of $1.48 for Q2, missing the analyst consensus estimate of $1.51. While this represents an 8.8% increase from the same period last year, it wasn't enough to satisfy market expectations. More alarmingly, the company's quarterly sales came in at $504.8 million, significantly below the analyst estimate of $552.87 million and marking a 10.37% decrease from $563.2 million in the previous year.

Adding to investor worries, Koppers revised its full-year 2025 sales forecast downward to $1.9-$2.0 billion, compared to the previous consensus estimate of $2.05 billion. The company now projects adjusted earnings per share for the fiscal year to be in the range of $4.00 to $4.60. Despite highlighting its ongoing "Catalyst" transformation process aimed at offsetting declining sales through cost-saving measures, the market reaction suggests investors are skeptical about the company's ability to navigate the challenging business environment in the face of declining sales volumes.