B − Hα cross correlation (DCF) statistics obtained from 2000 FR/RSS runs. The vertical red solid line denotes the median. The vertical red dotted area indicates the range inside the 68% confidence, and the blue vertical dotted lines give the formal 1σ uncertainty around the median. We note the low-τ peak, i.e., the strong signal at lag 60 days, about 20% shorthand of the median.