P&I (principal and interest)  

The term used to refer to regularly scheduled payments or prepayments of principal and of interest on mortgage securities.

Remarks: Bond funds including mutual funds (open-end and closed-end, actively managed and indexed), exchange-traded funds and unit investment trusts offer a convenient and affordable way to invest in a diversified portfolio of bonds, but a bond fund investment can differ from a bond investment in ways that are important to understand.