Daily fluctuation of funds = (net value of the day-net value of the last trading day)/net value of the last trading day × 100%, and investment income = fund holdings × daily fluctuation of funds-fund transaction costs. For example, the closing net value of the fund on that day is 1. In 5 yuan, the initial net value of the fund is 1. 4 yuan holds a fund of 6,543,800 yuan. Without considering the transaction cost of the fund, the fund income of that day = 10000× (1. 5- 1。 4)/ 1。 4× 100%=7 14。 3 yuan.

Fluctuation of funds held = (net value of funds on that day-net value at the time of fund subscription)/net value at the time of fund subscription × 100%, and investment income = amount of funds held × fund fluctuation-fund transaction cost. For example, the net investor value of a fund is 1. I bought 1 fund when I was in 5 yuan, and the net value of the fund was 1. When selling in 8 yuan, the transaction cost is 10 yuan, so the investor's holding income = 10000×( 1. 8- 1。 5)/ 1。 5×100%-10 =1990 yuan.

In addition, for some OTC funds, investors can calculate the income according to the following methods: net subscription amount = subscription amount /( 1+ subscription rate); Subscription fee = subscription amount-net subscription amount; Subscription share = net subscription amount on T day/net fund share; Redemption fee = redemption share × net value of fund share on T day × redemption rate; Redemption amount = redemption share × net value of fund share on T day-redemption fee; Net profit = redemption amount-subscription amount.