What it is:
Rolling returns are the returns on an investment measured over several periods.
How it works (Example):
The rolling returns on an investment are measured over a discrete number of consecutive periods (usually years) starting with the beginning of the earliest period and finishing with the end of the most recent. For instance, the two-year rolling return for 2008 would begin on 1 Jan 2007 and end 31 December 2008 (a full two years).
Why it Matters:
Rolling returns reflect the cumulative return on a continuously held investment over a number of consecutive periods.