Shares of Foothill Ranch-based Wet Seal Inc. fell about 7% in afternoon trading Thursday after the teen retailer lowered its earnings guidance for the February quarter.

The dip put the retailer’s market value at about $161.67 million.

Wet Seal, which operates 475 Wet Seal stores for teens and 57 Arden B stores for young women, saw a tough end to the year, with slowing foot traffic amid and heavy discounting.

The company said it’s now expecting a loss of $20.16 million for the quarter ended Feb. 1. That’s widened from previous guidance of a loss in the range of $11.76 million to $14.28 million.

Wet Seal said fourth-quarter net sales fell 22.8% to $124.8 million.

Sales of stores open at least a year slipped 16.5%.

Same-store sales for Arden B fell 25%, while the Wet Seal division fell 15.4%.

The company said it plans to hold a conference call to discuss its quarterly and full-year results on March 20.