Bearish sentiment from the Far East, combined with residual disappointment in Federal Reserve Chairman Ben Bernanke's comments yesterday, sent the S&P 500 Index (SNPINDEX:^GSPC) four points, or 0.3%, lower, to close at 1,650. That said, the S&P's three worst stocks of the day all suffered much more severe declines.

Cliffs Natural Resources (NYSE:CLF) slipped 3.6%, as the mining company felt the effects of weak industrial data from China today. The rapidly growing Chinese economy is the second largest in the world, and much of its growth relies on its manufacturing and industrial capabilities. The fact that its factory output decreased for the first time in seven months spells some potentially rough times ahead for Cliffs and other industry-reliant industries.

Regeneron Pharmaceuticals (NASDAQ:REGN), which has risen nearly 20% in the last month alone, slumped 2.9% Thursday. There doesn't seem to be much aside from mere profit-taking behind today's slip; yesterday, the stock actually edged higher on positive news from a joint project with Sanofi to develop an anti-asthma drug. The trial data showed a nearly 90% decrease in asthma aggravation in users who took the experimental drug vs. the placebo.

Freeport-McMoRan Copper & Gold (NYSE:FCX) rounds out the list of today's laggards, with a 2.3% loss. This is the third straight day of declines for the copper miner, which continues to struggle with market repercussions from a deadly mining disaster at one of its locations in Indonesia. The lost production from the closed mine is estimated to be around $15 million per day.

Fool contributor John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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