Most investors never stray beyond their borders. That’s a shame.Research shows U.S. investors keep 72% of their investments in U.S. stocks, and a third have nothing in international equities. Know that no single stock market has ever ruled the roost, so carrying a home-country bias can cost investors some long-term gains. In recent decades, the percentage of the world’s stock market capitalization comprised of U.S. stocks has dwindled, while emerging markets have rapidly grown. Since 1950, globally balanced portfolios have returned about 2% more than the straight S&P 500, with about 10% less risk. Global firms are usually more dividend-friendly, offering a nice alternative for the U.S.’s zero-interest-rate culture. And many analysts anticipate the U.S. dollar will decline, making appreciating currencies a salve. Since many advisors suggest keeping between 35 and 50% of a portfolio’s stocks in foreign companies, retail investors may want to access that exposure though an offering like the Vanguard Total International Stock ETF. It covers most of the world’s non-U.S. markets and contains thousands of stocks, without a big expense. The bottom line is adding international investments to your portfolio can have many benefits. And if you question the logic, just remember: even if you don’t have a Samsung phone in your pocket or a Honda in your driveway, your neighbor probably does.