Estimating S&P 500’s 2-Year Annualized Return 12 Months Into The Future

 | Sep 09, 2022 09:01AM ET

In a recent post I explored a methodology to guesstimate the S&P 500’s 2-year annualized return 12 months into the future. A silver bullet? Hardly, but as short-term forecasting models go you could do worse. But your editor gets poor marks for explaining the details. Several readers reached out and asked for clarification. Allow me to make amends.

The idea starts with taking the rolling 10-year annualized return for the S&P 500 Index and adjusting it by subtracting the one-year return, a.k.a. the 10-year/1-year return spread. History suggests this is a reasonable proxy for anticipating what the 2-year annualized return will be 12 months ahead.

Consider the relationship between the spread and the 12-months advanced 2-year return, per the chart below. The main takeaway: there’s a negative correlation between the two time series. It’s not perfect, but it persists enough of the time so that you should think through the reasons to ignore it in real time.