Markets seem to have already factored Japan's stimulus efforts into stock valuations. As a key member of the global economy, Wall Street cheered the country's announcement in April that it would double the amount of currency in circulation within two years in an effort to combat deflation. But today, after the Bank of Japan merely reiterated those plans, investors were unimpressed. The S&P 500 Index (SNPINDEX:^GSPC) lost 16 points, or 1%, dropping to 1,626 Tuesday. That said, three of the index's worst performers all had bigger problems on their hands.

First, shares of solar-energy player First Solar (NASDAQ:FSLR) plummeted 7.3% today, after the company announced the sale of 8.5 million shares of stock, a figure nearly 10% of outstanding shares on the market. It's no wonder current shareholders were so disappointed -- the company also said that some projects in Canada were behind schedule, which threatens the financial outlook for this quarter.

Peabody Energy (NYSE:BTU), which both mines and brokers coal, saw shares sink 4.3% Tuesday, as the U.S Interior Department addressed what it believes to be a consistent undervaluation of federally owned coal resources. The claims, that coal miners leasing federal land to mine the resource aren't paying fair prices for the right to do so, have obvious negative implications for companies like Peabody, which could see costs rise. 

Shares in Juniper Networks (NYSE:JNPR), which shot up 6.6% and 3.2% in separate days last week, came back down to Earth today, losing 3.8%. Wall Street cheered comments from the networking solutions company's CEO last Wednesday, as he suggested increasing demand from telecom customers. One factor pressuring shares today is the possibility Juniper gets in a bidding war down the line to acquire an IT security company in the wake of public outrage over the U.S. government's pervasive invasion of privacy.

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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