Packaging Corp of America (PKG) stock took a hit in the after-hours session on Tuesday, plunging 5.19% following the release of the company's mixed fourth-quarter results.

The packaging and containerboard company reported earnings of $2.47 per share for the quarter, missing analyst expectations of $2.53 per share by a narrow margin. However, PKG's revenue of $2.146 billion for the quarter beat estimates of $2.130 billion.

While the company saw a 10.73% increase in sales compared to the same period last year, investors appeared to focus more on the earnings miss. The mixed results likely raised concerns about PKG's ability to navigate rising costs and challenging economic conditions, leading to the after-hours sell-off in the stock.