31 CFR 205.20 - What is a clearance pattern?
States use clearance patterns to project when funds are paid out, given a known dollar amount and a known date of disbursement. A State must ensure that clearance patterns meet the following standards:
(c) A clearance pattern must include seasonal or other periodic variations in clearance activity.
(d) A clearance pattern must be based on at least three consecutive months of disbursement data, unless additional data is required to accurately represent the flow of Federal funds.
(e) If a State uses statistical sampling to develop a clearance pattern, the sample size must be sufficient to ensure a 96 percent confidence interval no more than plus or minus 0.25 weighted days above or below the estimated mean.