Whirlpool Corp., the world's biggest appliance maker, posted a 77 percent jump in quarterly profit on Friday as improved international results and a lower tax rate helped offset U.S. weakness, but sales missed expectations and its shares fell more than 4 percent.

Whirlpool backed its prior full-year profit forecast and said it expected performance in North America, its largest market, to improve in the second half as U.S. appliance demand rises.

Second-quarter net earnings rose to $161 million, or $2 a share, from $91 million, or $1.14 a share, a year earlier. Analysts on average expected $1.83 a share, according to Reuters Estimates.

It's phenomenal that Whirlpool is growing earnings the way that they are, but they clearly are being impacted by weakness in the U.S. and high steel costs, said Morgan Keegan analyst Laura Champine.

She added that a lower tax rate was a major reason earnings beat Wall Street estimates.

Whirlpool said it expected to realize cost savings of more than $400 million this year from its Maytag buyout, sooner than it had previously forecast. But it added that increases in materials costs would be higher than expected this year.

Total sales rose 2.5 percent to $4.85 billion, shy of the $4.95 billion analysts expected. Sales rose 10 percent in Europe, 29 percent in Latin America and 23 percent in Asia.

In North America, sales were down 6 percent at $3 billion because of lower appliance shipments and softer demand amid the cooling U.S. housing market. But operating profit in the region improved, helped by price increases and cost cuts from last year's Maytag buyout.

Although industrywide shipments of washers and other major appliances fell 1 percent in North America in the second quarter and 5 percent in the first half, Whirlpool noted that they began to improve in the period after months of declines. The company still expects U.S. industry shipments to fall 2 percent to 3 percent this year.

We are positive about the trends exiting the second quarter and believe (U.S.) demand will begin returning to moderate growth levels in the second half, Whirlpool Chairman Jeff Fettig said in a statement.

Whirlpool backed its prior forecast for full-year profit of $8 to $8.50 a share, saying higher U.S. demand, cost savings from Maytag buyout, new product launches and continued global strength would improve performance.

The Benton Harbor, Michigan, company said it now expected steel and oil-related costs to rise about $570 million this year, up from its view of about $500 million in April.

Whirlpool shares were down $5 to $111.66 in morning trading on the New York Stock Exchange. The stock has risen about 37 percent year to date, compared with a 25 percent rise in the S&P Household Appliances Index.