A unit investment trust's estimated return over the life of the portfolio, calculated according to formulas proposed by the Securities and Exchange Commission (SEC). The return is calculated as the annual percentage return based on the yields of all the underlying securities in the portfolio, but is weighted to account for each security's market value and maturity. The return is presented net of estimated fees and the maximum offering price, but does not account for delays in income distributions from the fund. 

|||When looking to invest in a unit investment trust, you will be shown both the estimated long-term return and estimated current return. The estimated long-term return may be the metric that you should look at if you are planning on investing for the duration of the trust. This will give a fairly accurate estimation of the return on the portfolio. It is similar to the yield to maturity measure of a single bond extended to a portfolio, with some adjustments.