"2014 was a record year in terms of net sales, volume and sales leader retention," Michael Johnson, Herbalife's chairman and CEO, said in the company's earnings release. "It was also a year of transition, as we continue to implement changes that we believe will create a stronger company with the ideal combination of growth and sustainability."
"We have seen the success of these changes in early adopter markets and remain confident that our other markets will follow a similar pattern through 2015 and beyond," he added.
Exchange rates took a major toll on the company's performance.
Herbalife's fourth-quarter worldwide net sales of $1.1 billion represented an 11 percent decrease from the same time in the prior year. Excluding currency impacts, however, net sales were flat compared to that same period, the firm said.
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The company revised its guidance in part because of the currency situation "faced by all global companies," Johnson said.
Herbalife said it expects a negative impact of about 28 cents to first quarter earnings, including approximately 10 cents resulting from Venezuela. For its full year guidance, the company said it expects a currency headwind of about $1.19, including approximately $0.45 from Venezuela.
The company said it expects first-quarter diluted earnings ranging from $1.00 to $1.10 per share. For fiscal year 2015, Herbalife guided for earnings from $4.10 to $4.50 per share.