Mattel Inc. (MAT - Get Report)  tumbled some 7% in after-hours trading Thursday after the troubled toymaker reported that fourth-quarter results sank by 262% compared to fourth-quarter 2016 net earnings, while 2017 full-year results plunged 431%. Mattel also swung from a profit to a loss for both the fourth quarter and 2017 as a whole when compared to year-earlier results.

"We have taken aggressive action to enter 2018 with a clean slate so we can reset our economic model and rapidly improve profitability," Mattel CEO Margo Georgiadis said in releasing the dismal results.

Still, the toymaker's stock plunged some 7% to $14.25 shortly before 8 p.m. ET in after-hours trading. The stock had already lost 3.28% during Thursday's regular session and is off nearly 50% from its 52-week high of $26.80.

Mattel said it lost $281.3 million in 2017's fourth quarter vs. a $173.8 million profit in the same 2016 period. That works out to an 82-cent-per-share loss per fully diluted share -- far worse than both the 15 cents per share in earnings that analysts had expected and fourth-quarter 2016's 50-cent-per-share profit. Fourth-quarter net sales also fell 12% to $1.61 billion, down from $1.83 billion a year earlier and below the $1.69 billion that analysts had expected.

For 2017 as a whole, MAT lost a whopping $1.05 billion, which represents a 431% downward swing from 2016's $318 million profit. The red ink works out to $3.07 per fully diluted share for the year as a whole -- way down from Mattel's 92-cent-per-share 2016 profit and far below the $2.05 that analysts had expected. Full-year net sales also fell 11% to $4.88 billion from 2016's $5.46 billion. 

Mattel -- which makes Barbie and American Girl dolls, Hot Wheels cars, Fisher-Price toys and other brands -- attributed part of 2017's losses to a $457 million noncash charge related to a valuation allowance on U.S. deferred tax assets in the wake of recent U.S. tax reforms.

The company said it also faced headwinds on many other fronts, including a recent Chapter 11 filing and massive store closings by retailer Toys "R" Us. The chain reportedly accounting for some 20% of Mattel's U.S. sales and 11% of sales internationally.

In addition, Mattel blamed poor North American results on tighter retailer inventory management and "certain underperforming brands." The company said that internationally, results suffered from "inventory-management efforts, unfavorable product mix, and higher freight and logistics expenses."

In January, Mattel agreed to sell Corrolle, a doll subsidiary, to Simba Dicke Group, a European toymaker. The same month, the company also offered $1 billion worth of eight-year unsecured bonds in a high-yield roadshow after reporting dismal Black Friday sales. S&P Global has cut Mattel's credit rating three times since July, most recently downgrading it to BB-.

(This article has been updated.)

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