J.C. Penney reported a deeper-than-expected drop in quarterly sales at stores open at least a year, the department store chain's second straight quarter of severe sales losses since changing its pricing strategy last winter.

Same-store sales fell 21.7 percent during the second quarter, steeper than the 17.4 percent drop analysts were expecting, according to Thomson Reuters. Revenue tumbled 22.6 percent to $3.02 billion, also below Wall Street's low expectations.

In February J.C. Penney [JCP  22.10    0.70 (+3.27%)   ] eliminated the use of coupons and discounts in favor of everyday low prices. The move has cost the 102-year-old retailer many shoppers.

Penney, whose customers are typically more price sensitive than those ofMacy's [M  38.12    0.11  (+0.29%)   ], reported a net loss of $147 million, or 67 cents per share, for the second quarter, ended July 28, compared with a profit of $14 million, or 7 cents per share, a year ago.