Rolling N-year average of quarterly data. Returns the mean of the last (N × 4) quarters — useful for 3-year or 5-year average ROE, margins, or growth rates.
Formula: avg(last N×4 quarterly values)
Long-window averaging is standard in quality-factor models. Warren Buffett famously looks at 10-year average ROE rather than a single year to separate structural profitability from cyclical spikes.