Net subscription amount = subscription amount ×( 1- subscription rate). This is called interpolation, which is intuitive and easy to understand.

Net subscription amount = subscription amount /( 1+ subscription rate), which is called external deduction method.

It is somewhat different in nature. The internal deduction method uses the subscription amount to calculate the handling fee, while the external deduction method uses the net subscription amount to calculate the handling fee, which is naturally different.

Deducted handling fee: subscription amount-subscription amount * subscription rate.

Deduction of handling fee: the formula of net subscription is simplified as multiplication, that is, subscription amount = net subscription amount+net subscription amount * handling fee.

Obviously, the external deduction method is a kind of protection for the interests of investors, so the CSRC has clearly stipulated that fund companies must use the external deduction method.