Shares of Corning Inc. GLW, +2.08% were off more than 5% in premarket trading Tuesday after the manufacturer of glass products delivered a lower-than-expected outlook for the current period as it waits to forecast a significant recovery in demand for glass. The company recorded third-quarter net income of $208 million, or 24 cents a share, down from $371 million, or 43 cents a share, in the year-before period. Corning’s “core” earnings per share, an adjusted metric, came in at 51 cents, down from 56 cents a year earlier but in line with the FactSet consensus. Sales fell slightly to $3.49 billion from $3.62 billion. FactSet doesn’t provide consensus estimates for Corning’s sales on the basis of generally accepted accounting principles (GAAP). “As we told investors in early September, panel makers reduced their production levels below our already low expectations,” Chief Financial Officer Ed Schlesinger said in a release. For the fourth quarter, Corning expects “core” sales, or adjusted sales, of $3.45 billion to $3.65 billion, along with “core” or adjusted EPS of 41 cents to 47 cents. The FactSet consensus was for $3.75 billion and 55 cents, respectively. “Although we believe that panel maker utilization reached the bottom in September, we would like to see more evidence before we guide a significant recovery in glass demand,” Schlesinger said. “When glass demand does increase, we expect our volume to return and company profitability to improve.” Corning shares have lost 13% so far this year as the S&P 500 SPX, -0.74% has declined 20%.