New York (CNN Business) Harley-Davidson has a big problem. Americans aren't riding its trademark hogs nearly as much as they used to do.

Harley-Davidson HOG Shares offell 3% in early trading Tuesday after the company reported sales and earnings that missed Wall Street's forecasts. The stock is now down more than 10% this year.

Most alarming: Demand for Harley's bikes continued to fall in the United States -- even as they rebounded overseas.

Harley's retail sales in America were down 3% in the fourth quarter. That's the 12th consecutive decline. US sales fell more than 5% for the full year.

Sales were up slightly internationally, led by a more-than 6% jump in Asia. But that wasn't enough to lift Harley's worldwide motorcycle sales, which fell 1.4%.

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