T+2 fund is a transaction settlement method, that is, it takes two working days to settle the transaction funds after purchasing or redeeming the fund. The rise and fall are judged according to the changes in the net value of the fund. In T+2 fund, investors can judge the rise and fall of the fund by observing the change of its net value.

Generally speaking, the rise in the net value of T+2 fund means that the market value of assets held in the fund portfolio rises or dividends, which leads to the increase in the net value of the fund. On the contrary, if the net value of a T+2 fund falls, it means that the market value of assets held in the fund's portfolio falls or there is redemption behavior, which will lead to the decline of the fund's net value.

Investors can observe and analyze the rise and fall of T+2 funds in the following ways:

1. View the historical net worth chart of the fund: investors can understand the rise and fall of the fund by observing the historical net worth chart of the fund. If the net value shows an upward trend, it means that the fund may rise; If the net value shows a downward trend, it means that the fund may fall.

2. Analyze the performance of the fund: investors can observe and analyze the performance of the fund, including the comparison with similar funds and benchmark indexes, as well as the risk-return characteristics of the fund. If the fund performs well and ranks high among similar funds, it may mean that the fund has great growth potential in the future.

It should be noted that investment is risky, and the rise and fall of funds are related to investors' expected returns, and are also affected by market supply and demand, macroeconomic environment and policies. Therefore, for specific T+2 funds, investors need to comprehensively consider personal risk preferences, investment objectives and time, and make reasonable investment decisions.