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For a while, it looked as if social media stocks were going to be the next hot buy, the first real wave of equities that got not just hardcore investors but the general public excited about them. This period ended about the time Facebook had its IPO – the most anticipated public stock offering in a decade, and the biggest in terms of dollar amount that America had ever seen – back in May.

See also: America’s 10 Biggest IPOs

Since then, it’s been pretty much all downhill for social-media stocks. In a sense, they seem to be creating a miniature version of the Internet stock bubble, which ran for several years before investors figured out that companies with little or no earnings were not worth paying a premium price for. The Internet has grown ever more significant in people’s lives since then, but companies working that space have come to be far more rationally valued. 

Similarly, social media as a phenomenon shows no signs of fading – but the stock frenzy sure does. Here’s what’s happened to the most prominent social media stocks this year:

Facebook

Facebook launched its much ballyhooed IPO on May 18, just days after increasing the initial price from $34 to $38 a share. But the problems started almost immediately: The stock debuted on the Nasdaq exchange a half hour late due to technical problems, and other technical glitches hampered traders all day long. Still, at the end of the day, Facebook boasted a larger market cap than McDonald’s or Disney.

Ever since then, the news has been disappointing. Last week’s earnings report provided the latest down moment: Sales grew at 32 percent in the second quarter, down from 45 percent in the first quarter. Many companies provide guidance for future sales or profit growth when they report earnings, but Facebook declined to do that, which didn’t help investor confidence. Even though it did edge past its earnings estimate, reporting $1.18 billion as opposed to the consensus figure of $1.16 billion, on the day it reported earnings, Facebook dropped 6.2 percent.

The stock has fallen in an orderly fashion, from that first day’s close just over $38 all the way down to around $20 now. And with Facebook’s lockup period ending this month, insiders are expected to dump as many as 200 million additional shares onto the market, which could depress the price even further.

Google obviously thinks Facebook’s dominance in the social-media space is looking vulnerable. Just this week, Google+, the search giant’s social-media arm, acquired a social advertising firm called Wildfire Interactive, which had claimed Facebook as its primary client. To stick its thumb in Facebook’s eye even further, Google’s new subsidiary is where Arielle Zuckerberg — Mark Zuckerberg’s little sister — works.

Zynga

Zynga has been sort of a sister company to Facebook, providing ridiculously addictive games like FarmVille for the site’s users. Zynga went public back in December of 2011, but instead of the hoped-for first-day pop, the shares came out and promptly dropped 5 percent. It might have been worse, except that the stock’s underwriters put in a stabilizing bid to shore up the price.

After closing the first day at $9.50, Zynga managed to peak at $14 on March 7. But then Facebook’s IPO provided another hit to Zynga’s value. When the first-day pop wasn’t there for Facebook, either, investors lost confidence in Zynga as well. When Facebook came out and simply treaded water on that first day, Zynga dropped 13 percent.

And the bad news kept on coming: Zynga fell short of its earnings estimates — something less than 40 percent of all companies do — this past quarter, and then was hit by a lawsuit from an investor who charges that Zynga has been misleading about its financial prospects. The stock is now down under 3, a loss of more than 70 percent from its opening price, less than nine months ago.

Groupon

Unlike Facebook and Zynga, deal-of-the-day couponing site Groupon performed well out of the gate, rising more than 50 percent on the day of its IPO back in November 2011. But within three weeks it had given all that back, dropping below its first-day price.

And the stock has been on a long, slow slide all year. From a high of $24 in February, the price his trickled all the way down to $6 this week. Groupon is now off a whopping 75 percent from its opening day.

LinkedIn

That leaves LinkedIn as the success story among the social-media stocks. It was the first of these stocks to have its IPO, back in May of 2011, and the only one to get the kind of pop they were all looking for. The IPO price was set at $45, but the shares opened at $83, a jump of 83 percent that had people looking back to the days of eToys and Google. LinkedIn’s stock closed that day at $94.25, for a 109 percent pop.

And LinkedIn has, for the most part, been able to stay at those lofty levels. There have been a few roller-coaster rides — down to 63 last June, peaking at 110 in July, dropping back down to 59 in November, then peaking again at 117 this May — but no sustained free-fall. After handily beating earnings estimates in its report yesterday, and raising its full-year revenue forecasts, LinkedIn rose 6 percent after-hours to as high as $99, or ahead of where it finished on its IPO date.

Yet there are reasons for concern. LinkedIn’s forward price-to-earnings ratio remains an unsustainably lofty 75. Its price to sales ratio is almost identical to that of Facebook, despite the fact that Facebook’s market cap is about four times as large as LinkedIn.

Perhaps, after Facebook’s share value has had time to complete its own roller-coaster ride, it may be that the biggest difference between the two stocks is that Facebook overvalued its IPO while LinkedIn undervalued its IPO.