The S&P 500 Index (SNPINDEX:^GSPC) retreated from the all-time highs it reached yesterday, as a trace of bearishness returned to the stock market today. Although both factory orders and motor vehicle sales came in higher than expected, the three major U.S. indices each fell, and Wynn Resorts (NASDAQ:WYNN), Cliffs Natural Resources (NYSE:CLF) and E*Trade Financial (NASDAQ:ETFC) finished as the three worst performers in the S&P 500. The benchmark index itself didn't take much of a hit, losing less than a point, or less than 0.1%, to finish at 1,924.

Wynn Resorts fell, along with many of its peers in the gaming industry, losing 4.5% Tuesday. Up until very recently, investors associated the big casinos with a few, well-established gambling meccas like Las Vegas and Atlantic City. But things have changed, and now Macau, the only location in China where gambling is legal, dwarfs the business Las Vegas and Atlantic City every year. Wynn has shrewdly established itself in Macau, but since Macau hasn't fully defined itself yet, Wall Street never knows quite what to expect from it. Wall Street certainly wasn't expecting May Macau revenue to rise by "just" 9.3%, a figure that missed median estimates by about 5%.

Cliffs Natural Resources fell 4.3%, as the stock continues to reel from a public spat with an activist investor who's really embracing the whole "active" thing. Casablanca Capital wants to break the company into two separate parts -- one with Cliffs' U.S. division, the other with its international operations -- in an effort to create more shareholder capital. Last week the stock took a hit after a Barron's article said the quarrel with Casablanca is actually hurting shareholder value. My colleague Vladimir Zernov agrees, arguing that several of Casablanca's demands aren't even feasible.

"The E*Trade Baby" bidding patiently at an auction. Source: E*Trade.

E*Trade Financial tumbled 3.9% on Tuesday after the company released numbers showing a troubling decline in customer activity. Every month the online brokerage reports changes in customer account values, cash inflows and outflows, and the most-watched of all, daily average revenue trades, or DARTs. E*Trade shareholders like to see the average portfolio size grow, of course, and welcome converts to the brokerage with open arms. But if investors aren't trading, E*Trade isn't making money. E*Trade's May DARTs came in around 148,000, or about 14% less than April DARTs, a concerning sign for investors.

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