Realty Income (O 0.95%) is the world's seventh largest real estate investment trust (REIT), with $59 billion of real estate across eight countries. The company's large and diversified portfolio generates stable and growing cash flow. That gives it money to pay dividends and invest in expanding its global real estate portfolio. The REIT has a lot going for it these days. Here are three reasons to consider adding Realty Income to your portfolio this year. This REIT has a lot of attractive investment qualities ...