Mutual funds can’t assure returns. But, debt fund investors typically like a certain degree of surety. Then, can we predict the returns debt funds could give? All such funds disclose the average yield-to-maturity; the average of yields of all bonds held. Deduct the expense ratio of the bond scheme from the average yield-to-maturity, and you get the net yield. This net yield gives an indication of how much money you will make if your time frame matches the duration of the portfolio. But this is an indicative approach, for schemes that follow roll-down strategies and target maturity plans. For actively-managed debt schemes, large inflows and outflows can change yields sharply.