The rise and fall of the fund is expressed as a percentage, and the rise and fall during the period = (final value - initial value) / initial value. The questioner can substitute the price to calculate the specific income amount.

The daily increase or decrease of the fund is mainly calculated based on the fund's net value. The daily increase or decrease of -0.1% means that today's net value is 0.1% lower than yesterday. If the fund's net value was 1 yesterday, today it is 1- 1*0.1%=0.99. If the net value of the fund decreases, more shares can be purchased with the same amount. Similarly, the amount held will decrease, which means a loss.

Fund, in English, is fund, which broadly refers to a certain amount of funds established for a certain purpose. It mainly includes trust investment funds, provident funds, insurance funds, retirement funds, and various foundation funds.

From an accounting perspective, funds are a narrow concept, meaning funds with specific purposes and uses. The funds we mention mainly refer to securities investment funds.