It's no surprise that international stocks have gained popularity with investors over the past few years. They've generated absolutely amazing growth.

For the past six years in a row, the Vanguard Total International Stock Market Index outpaced the Vanguard Total Stock Market Index. The latter tracks just the broad U.S. market, including top holdings in Pfizer (NYSE:PFE) and Verizon.

Even though foreign markets probably won't outperform U.S. markets every year, international stocks are undeniably worth your time to research. And thanks to American Depositary Receipts (ADRs), U.S. investors have more opportunities than ever to trade foreign securities on domestic exchanges.

This month's best performances
Foreign companies that participate in an ADR program must file reports in accordance with U.S. regulations, but their different corporate cultures and business decisions can seem unorthodox to American investors.

To help us understand this month's top-performing ADRs, we'll tap the expertise of more than 105,000 investors participating in Motley Fool CAPS, the Fool's free investing community. Here are the top six performers over the past month among ADRs, along with their ratings from the CAPS community.



1-month % Change

CAPS Rating
(out of 5)

VanceInfo Technologies (NYSE:VIT)




China Finance Online (NASDAQ:JRJC)




ReneSola (NYSE:SOL)








China Sunergy (NASDAQ:CSUN)




VisionChina Media (NASDAQ:VISN)




Data provided by Capital IQ, a division of Standard & Poor's, and Motley Fool CAPS as of May 16; screen excludes companies with market cap of less than $100 million.

Hmm. I see a trend here.

Remember, I chose these stocks as jumping-off points for further research, not as formal recommendations. That said, the CAPS four- and five-star ratings for stocks such as these are an effective tool for investors.

Why they rallied
VanceInfo Technologies: The Chinese outsourcing company produced its own blowout quarter, with first-quarter net revenue growing an astounding 96.5% year over year. Net income grew even faster, at 138.3%.

China Finance Online: China Finance's management upped its first-quarter revenue and earnings guidance last week as a sign to investors that the company's growth prospects remain healthy. Not all CAPS players agree, however. Fully 41% of CAPS All-Stars think China Finance will underperform the S&P 500 going forward. You can see their reasoning by clicking here.

ReneSola: As CAPS player slm05k summarized on Friday, the beaten-up Chinese solar company "reports blowout quarter, raises guidance and stock goes straight up." Slm05k thinks ReneSola's rebound will continue as well, further noting, "Only thing is it is still under valued and they have a great management team that is cost efficient. I like this company the best in the solar wafer market."

GPC Biotech: The stock price jumped 58% on May 7, likely due to a rumor that it was going to merge with Wilex. However, the company hasn't commented. CAPS player zzlangerhans summed it up with, "I think it's safe to assume that the sudden doubling of share price was due to a leak or rumor about a merger with Wilex, rather than a sudden realization that the pipeline was undervalued. I don't see satraplatin and the kinase inhibitors being worth the newly inflated market cap to anyone."

China Sunergy: Over the past month, the heliocentric company has been an indirect beneficiary of positive earnings reports from other major players in the solar sector, like JA Solar and Canadian Solar. It's this company's turn to report tomorrow, though, and given its three-star CAPS rating, it seems like investors are torn on its prospects. One China Sunergy bull is TMFSarahGen, who thinks this stock is a strong sector play: "Solar could not be hotter - with all three potential presidential candidates supporting solar. And solar growth happening around the world - recent reports from others in the sector ([Canadian Solar] and [Applied Materials] most recently) show the strength in this sector."

VisionChina Media: The Chinese advertising company’s share-price surge earlier this month is attributed to a positive mention in the May 2 online edition of Investor's Business Daily. The article noted that VisionChina, among other Chinese media companies, stands to profit from the coming Olympic Games in Beijing with its real-time televised advertisements found in public-transit vehicles.

What do you think?
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