The study looked at G7 stock prices to see if they follow a random pattern or if they tend to revert to a certain level over time. They used tests that allow for changes in trends to analyze the data. The results show that only Japan's stock prices show some evidence of reverting to a mean level, while the other countries' stock prices mostly follow a random walk pattern. The study also found that the second break in stock prices has negatively affected their movements in the G7 countries.