Questione giuridica chiave
Whether the cessation of gainful employment constituted a material change justifying revision under Art. 17 ATSG.
Decisione estratta
Yes. Once no gainful activity remained, the invalid income had to be assessed on an abstract basis, which amounted to a relevant change in the factual basis for revision.
Motivazione estratta
A revision ground exists whenever a significant change in the circumstances since the original award can affect the degree of disability. The move from an actual earned income to a hypothetical income based on average values is sufficient; a changed work percentage is not required.