There is no formula for calculating the rate, which is set by the fund company itself.

The calculation formula of your purchase share is: 30w/( 1+ 1.5% subscription rate)/your net value at the time of purchase.

The calculation formula of your total assets is: the share you hold × the net value of the fund on that day.

If you choose to redeem, the money you get = total assets on the day of redemption × (redemption rate 1-0.5%).