20 CFR § 404.1574a - When and how we will average your earnings.
(a) If your work as an employee or as a self-employed person was continuous without significant change in work patterns or earnings, and there has been no change in the substantial gainful activity earnings levels, we will average your earnings over the entire period of work requiring evaluation to determine if you have done substantial gainful activity. See § 404.1592a for information on the reentitlement period.
(b) If you work over a period of time during which the substantial gainful activity earnings levels change, we will average your earnings separately for each period in which a different substantial gainful activity earnings level applies.
(c) If there is a significant change in your work pattern or earnings during the period of work requiring evaluation, we will average your earnings over each separate period of work to determine if any of your work efforts were substantial gainful activity.
(d) We will not average your earnings in determining whether benefits should be paid for any month(s) during or after the reentitlement period that occurs after the month disability has been determined to have ceased because of the performance of substantial gainful activity. See § 404.1592a for information on the reentitlement period. The following examples illustrate what we mean by a significant change in the work pattern of an employee and when we will average and will not average earnings.
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