Life-Weighted Average:

When TIP$TER calculates a "life-weighted average" of a statistic – for example, the life-weighted average retirement budget – TIP$TER weights each value in annual time series by multiplying it by the probability of either you or your spouse, if any, surviving to experience that event.  TIP$TER then divides the sum of these weighted values by the sum of the weights.  This yields a statistic that proportionately weights values from the early years of the simulated portfolio over the later years of the portfolio.