Analyst earnings forecast revision ratio, by calculating the difference between the number of institutions that raised and lowered EPS forecasts and the ratio of the total number of institutions, quantifies the attitude of analysts towards the changes in the company's future earnings expectations. This indicator reflects the market sentiment and expectations of changes in the company's fundamentals: a positive value indicates that analysts have raised their earnings forecasts overall, indicating that the market is optimistic about the company's future profitability; a negative value indicates that the earnings forecasts have been lowered overall, indicating that the market attitude is pessimistic; the higher the absolute value, the greater the expected change and the more drastic the market sentiment fluctuations. This factor can be used as an important tool to capture changes in market sentiment and earnings expectations, and has a certain reference value in quantitative stock selection and investment decisions.