NEW YORK, United States — Quiksilver Inc., the maker of surf clothing and other athletic wear, plunged the most in almost three decades after posting a wider loss and forecasting sluggish sales for the rest of the year.

Excluding some items, the loss widened to 15 cents a share last quarter, the Huntington Beach, California-based company said yesterday in a statement. Analysts had estimated a 2-cent loss on average, according to data compiled by Bloomberg. Revenue declined 11 percent to $408 million, missing the $448.8 million predicted by analysts.

Quiksilver is facing shrinking sales in North America and Europe -- a trend the company expects to continue through the second half of fiscal 2014, which ends in October. Following the earnings report, analysts at Stifel Financial Corp. and other firms downgraded the stock.

The shares tumbled as much as 45 percent to $3.18, marking the biggest intraday decline since the company’s initial public offering in 1986. The stock had already dropped 34 percent this year through yesterday, dragged down by concern the company was struggling to turn around the business.

By Nick Turner; Editors: Nick Turner and Bruce Rule