《明史·志·卷八》
下法乘以初商，再用正寅减去此数，如正赏不够减，就改用初商。
下法乘初商，以减正实，实不足减，改初商。
Multiply the lower method by the first quotient, then subtract this number from the correct yin. If the correct reward is not enough to subtract, then switch to the first quotient.