Aug. 31 (Bloomberg) -- So far this year, Sweden’s OMX Stockholm 30 Index is up about 53 percent, in dollar terms. London’s FTSE 100 Index has gained 24 percent. Benchmark indexes in Germany and France are up about 18 percent. By contrast, the Standard & Poor’s 500 Index of U.S. stocks has risen about 14 percent this year while the 30-stock Dow Jones Industrial Average has managed an increase of less than 9 percent. International diversification usually helps your portfolio’s performance in years when U.S. companies lag behind. Also, the wider the universe from which you select stocks, the better your chance of finding bargains. To be sure, during a financial crisis, as we saw last year, foreign stocks can sink along with U.S. securities -- or do worse. This week I am recommending a few European stocks. Later this year, I will look at opportunities in Asia. Most American investors, of course, primarily buy U.S. stocks. The so-called home market bias exists across the world, which is natural. People like to bet on companies they know about, so they gravitate to their home market. Financial disclosure requirements in the U.S. are, in my opinion, superior to those of most other countries. For example, U.S. investors can search Securities and Exchange Commission filings to learn whether insiders are buyers or sellers of a company’s shares. Buy Them Here For foreign companies traded as American depositary receipts, or ADRs, this information isn’t available. It is, however, accessible for those with direct listings on a U.S. exchange. I recommend that most U.S. investors use 15 percent to 20 percent of their stock-market capital to buy shares in foreign companies. The securities mentioned here can be bought in the U.S., either through direct listings or through ADRs. We’ll start with CRH Plc, the world’s No. 2 maker and distributor of building materials. This Dublin- based company operates in 35 countries, making cement, concrete, roofing, insulation and other building products. It also has 471 stores serving contractors in five European countries and another 246 aimed at do-it-yourselfers, according to the company’s Web site. CRH was banged up a bit by the worldwide recession of 2008. Earnings dropped about 11 percent last year. But over the past five years, sales and earnings have been increasing a bit more than 14 percent annually. Goodbye Houston Next let’s look at a pair of energy stocks that are recent transplants to Europe, Weatherford International Ltd. and Transocean Ltd. Both companies formerly were based in Houston and moved to Switzerland. Weatherford is located in Zug, and Transocean in Vernier. At one time Transocean was based in the Cayman Islands and Weatherford in Bermuda. It seems to me that both companies chose their headquarters for tax reasons. I believe the moves to Switzerland were sparked by an expectation that the Obama administration will reduce the tax advantages of operating in certain countries known as tax havens. Weatherford is the world’s largest seller of so- called artificial lifting technology, which enhances the flow of oil from a well. It also produces equipment that can operate underwater at extreme depths, where the pressure is intense. Good Values Analysts expect Weatherford to earn only 71 cents a share this year. In the three previous years, it earned more than $1 a share, and hit $2 a share, excluding abnormal items, in 2008. With the stock at about $21, it is not especially cheap, but it is probably reasonably priced. The average price- earnings ratio for the past six years was 25. Transocean is the world’s largest offshore driller. Its fleet includes 136 rigs, 20 of which are designed for the deepest ocean waters. Analysts guess than Transocean will earn $12 a share this year, down 16 percent from 2008 but still the company’s second best year. At about $78 a share, the stock sells for only six times expected earnings, and less than six times trailing earnings. That is my kind of multiple. Another Swiss company I like is Ace Ltd., a reinsurer based in Zurich. Analysts expect it to earn more than $7 a share this year (before abnormal, or extraordinary, items), for the fourth year in a row. Yet the stock sells for about $52, just seven times expected earnings. One more Swiss company I’m fond of is Nestle SA, based in Vevey. The world’s largest food company is highly profitable, having racked up a 35 percent return on equity last year, and yet sells for less than nine times earnings. Greek Shipper Rounding out my list with a more speculative pick, I recommend a small Greek stock, Stealthgas Inc., based in Athens. Among the risk factors: Its market capitalization is only $112 million, and it has been public only since 2005. Stealthgas transports liquefied petroleum gases, such as propane and butane, by ship. Revenue last year was $112 million, up from less than $37 million 2005. Yet the stock price today, at about $5 is less than half the initial offering price of $14.50. The stock, traded on Nasdaq in the U.S., sells for only four times earnings, one times revenue and 0.4 times book value. CRH and Nestle trade as ADRs; the others are listed directly on U.S. exchanges. Disclosure note: For clients and personally, I own shares of Nestle and Transocean. I currently have no long or short positions in the other stocks discussed in this week’s column. (John Dorfman, chairman of Thunderstorm Capital in Boston, is a columnist for Bloomberg News. The opinions expressed are his own. His firm or clients may own or trade securities discussed in this column.)