Woodside Petroleum reported a 9% drop in first-quarter revenue on April 20 as production fell, largely due to extremely heavy rainfall, but stuck to its full-year production forecast.

Revenue in the March quarter fell to $895 million from $982 million a year earlier, while production fell nearly 10% to 21.4 million barrels of oil equivalent (MMboe).

The result was well below a forecast by Royal Bank of Canada for revenue of $996 million.

Woodside stuck to its forecast for full-year production between 84 MMboe and 90 MMboe, and said it was working with partner Chevron Corp. (NYSE: CVX) to ensure the Wheatstone LNG project starts producing mid-year.