In a recent analysis, financial experts concluded that investing in renewable energy stocks is the best strategy for achieving long-term financial growth. They cited that global demand for clean energy is expected to increase significantly due to government policies and growing consumer preferences. However, critics point out that past performance does not guarantee future results, and other investment sectors, such as technology or healthcare, also show promise. Based on this analysis, which of the following would be most necessary to evaluate the strength of the experts' conclusion?