The article explores how changes in companies' book-to-market ratios over time can help explain why some stocks perform better than others in global markets. By looking at factors like stock performance and equity issuance, researchers found that predicting future returns is strongest in developed markets. A strategy of investing in companies that buy back stocks and selling those that issue more shares has yielded a significant annual premium over the past 25 years. This strategy also helps explain why some value and glamour stocks perform better globally.