Packaging Corporation of America (PKG) reported Q1 non-GAAP net income late Tuesday of $2.31 per diluted share, up from $1.72 a year earlier.

Analysts polled by FactSet, on average, expected $2.21.

Net sales for the quarter ended March 31 were $2.14 billion, up from $1.98 billion a year earlier.

Analysts expected $2.11 billion.

Shares of Packaging Corporation of America were down over 6% in after-hours trading.