UPDATE 2-Yingli cuts margin forecast, shares fall

* Net loss 44 cents per share

* Revenue falls 25 pct to $219.5 mln

* Shares slide as much as 15 percent (Recasts with margin details, analysts' forecasts, share price)

NEW YORK, Aug 19 - Chinese solar energy company Yingli Green Energy Holding Co Ltd on Wednesday posted a quarterly loss and cut its profit margin forecast, sending its shares tumbling as much as 15 percent in early trade.

The Baoding, China-based company said its gross margin for the year would be between 18 and 20 percent, down from the 23 to 25 percent it had predicted in May. It said its second-quarter gross margin was 18.3 percent.

Solar panel makers have suffered this year from a falloff in demand due to a lack of financing for projects and a pullback in government incentives in Spain. That drop in demand has led to an oversupply of solar panels that has sent prices, and producers' profits, tumbling.

Net loss was $57.6 million, or 44 cents per American Depositary Share, compared with a profit of about $29.8 million a year earlier.

Excluding one-time charges linked to an early debt retirement, Yingli's earnings of 6 cents per share topped analysts' average forecast of 2 cents per share, according to Reuters Estimates.

Revenue fell 25 percent to $219.5 million. Analysts had been expecting revenue of $210.6 million, according to Reuters Estimates.

Like other solar companies, Yingli saw its average selling prices slide in the second quarter as the weak financing market and glut of supplies weighed on the market.

Yingli stuck to its forecast for full-year shipments of 450 to 500 megawatts of solar modules, an increase of as much as 78 percent from 2008.

Shares in Yingli slumped as much as 15 percent to $9.97 per share in early trade on the New York Stock Exchange before slightly paring losses to trade down 11 percent at $10.47.