The SEC Yield, otherwise known as the Standardized Yield, is a standard yield calculation developed by the US Securities and Exchange Commission for investors to be able to compare different bonds. It is the annualized return rate of the bond over the course of a 12-month period, based on the most recent distributions, minus the net investment advisory fees.

The SEC Yields of different bonds is calculated differently, but the same concept applies to them all. It gives investors a clear indication of what they will get in return if they invest in the fund over the next 12 months. In other words, it serves as a measure of the fund's investment performance over the previous period.

The SEC Yield is calculated by taking the total amount of the bond's distributed payments over the past 12 months, and dividing it by the average net asset value of the fund. This is then multiplied by the 12-month output figure to come to the final figure. It is important to note that the annualized return does not take into account fees, taxes or expenses associated with the investments.

The SEC Yield is an important tool for investors to assess the performance of various bonds over a period of time. It can give them a good indication of the yield that they can expect from their investments, as well as help them to compare various funds and investment options.

Overall, the SEC Yield is an essential tool for investors looking to compare the performance of different bonds. It offers a fair comparison of different bonds and gives investors a fair idea of the expected yield for the coming year. It is important to keep in mind that the annualized return does not take into account any fees associated with investing in a particular bond, so investors should always do their homework and consult a professional before making any investment decisions.