SAN FRANCISCO -- eBay ( EBAY) did little to allay investor concerns on Wednesday, offering a fourth-quarter forecast that's well short of Wall Street expectations. Shares of eBay, which plunged more than 13% on Wednesday, fell another 4.2% in recent after-hours trading to $14.69. The online auction site posted third-quarter earnings of $492 million, or 38 cents a share, compared with a loss of $936 million, or 69 cents a share, in last year's quarter, which included a hefty goodwill impairment charge. Excluding certain items, eBay posted earnings of $592 million, or 46 cents a share. That topped analysts' expectations of 41 cents a share, and above the company's own guidance. Revenue, however, fell short of Wall Street estimates, totaling $2.12 billion. Analysts were expecting revenue of $2.13 billion. eBay also reported a 1% decline in gross merchandise volume in the third quarter. That marked a significant decline from the second quarter, when gross merchandise volume was up 8%. "Overall, we are pleased with the performance of the portfolio this past quarter," said eBay CEO John Donahoe in a statement. "We took a number of steps during the quarter to further strengthen our business and better align our cost structure to invest and compete. We will continue to stay focused on connecting consumers on our various ecommerce platforms, maintaining financial discipline and capitalizing on new opportunities for growth." For the fourth quarter, eBay expects revenue to range between $2.02 billion and $2.17 billion and earnings in the range of 39 cents a share to 41 cents a share. That was much lower that Wall Street predictions for revenue of $2.44 billion and earnings of 47 cents a share.