The top-down strategy starts with the macro situation and the characteristics of industries and sectors, defines the allocation of assets, countries and industries, and then selects the corresponding stocks as investment targets to achieve the allocation goal. Fund managers' prediction of macroeconomic situation is a top-down strategy. Bottom-up is an investment strategy that depends on the selection of individual stocks, focusing on the performance of each company, rather than the overall trend of the economy or market, so bottom-up does not pay attention to industry allocation.