Check out the companies making headlines in extended trading.

CSX — The transportation company’s shares were up 2.6% after the company’s first-quarter earnings and revenue topped analysts’ expectations. CSX posted earnings of 48 cents per share and revenue of $3.71 billion. Analysts polled by Refinitiv had anticipated earnings of 43 cents per share and $3.58 billion in revenue.

Knight-Swift Transportation — Shares fell less than 1% after the freight transportation company reported a miss on earnings for the first quarter. The company reported adjusted earnings of 73 cents per share, while analysts estimated per-share earnings of 81 cents, according to FactSet. However, the company’s revenue of $1.64 billion came above analysts’ expectations of $1.61 billion. Knight-Swift also cut its full-year EPS guidance for 2023.

W.R. Berkley — Shares of the commercial lines insurer slipped 2% after W.R. Berkley reported net premiums that were lower than analysts’ estimates, coming in at $2.49 billion versus expectations for $2.53 billion, according to FactSet. The company posted operating earnings-per share of $1.00, compared to $1.10 per share a year ago.

PPG Industries —The paint manufacturer’s stock gained less than 1%. The company issued second-quarter guidance that came in ahead of analysts’ expectations, according to FactSet. PPG anticipates adjusted earnings will be $2.05 to $2.15 per share, compared to analysts’ estimates of $1.96 per share. PPG also issued rosy guidance for the full year.