you can't buy a fund that has been falling. From the trend point of view, it is very risky to buy a fund in a downward trend. You need to wait until the trend reversal shows obvious bottom characteristics before buying a fund. In addition, the fund that has been falling may be due to the management problems of the fund itself or the serious losses of the fund, so you can't buy such a chicken essence during the decline.
What is the formula for calculating the implied rate of return of graded fund A?