This factor essentially measures the change in the market's expectations for a company's future earnings, as reflected in the extent of the adjustment in the price-to-earnings ratio. A positive value indicates that the current expected price-to-earnings ratio is higher than three months ago, which may mean that the market's optimistic expectations for the company's profitability have increased, but it may also reflect that the increase in stock prices has exceeded the increase in earnings expectations, and there is a certain valuation premium risk. Negative values ​​are the opposite. This factor can be used to identify situations where valuations diverge from earnings expectations and assist in judging investment opportunities or risks. It should be noted that the expected price-to-earnings ratio itself is affected by the accuracy of analysts' forecasts, so the effectiveness of this factor also has certain limitations. At the same time, in extreme cases, if the expected price-to-earnings ratio three months ago is close to zero, the factor will fail, so extreme values ​​need to be processed when used.