(1) The period of time used to compute the annualized rate of return of particular indexes or composites in a technique that allows users to see longer term trends.
(2) The length of time between the beginning of one cycle and the start of the next. The rolling period is expressed in units corresponding to the periodicity of the chart. Also called the gap length.[@more@]
example:
Every employee (including long-term secondees and VIEs) must take Block Leave at least once in a 12-month rolling period.