We can use the range of 3000 to 4000 points as the benchmark for fixed investment. If it exceeds this range, our investment will be reduced. If it falls below this range, we will invest more. First, we need to set a benchmark for the fixed investment index. This indicator point should not be set too high or too low, and it is best to be in the middle. Based on the index data, a certain number of slices are set up above and below the index respectively.