Yield to worst (YTW) is a measure that helps investors determine the minimum interest rate they can earn on a bond if they hold it until maturity, assuming no default on payments. YTW is calculated by considering the worst-case scenario during the bond's term, such as early prepayment or bond calls.
When assessing a portfolio of bonds, YTW can be used to evaluate the portfolio’s overall yield at a specific point in time. The portfolio's YTW is calculated by taking the weighted average of the YTWs for all the bonds in the portfolio. This provides investors with valuable insights into the risk and return potential of their overall bond portfolio.
"Yield to worst" should not be seen as expected return, but it provides an overview of the current return on the underlying investments of the fund, before any withdrawal of fees and costs related to currency hedging. The measure also does not take the prices of bonds and currency exchange rates into account.