Kernrechtsfrage
Whether the relevant comparison period for pension revision was 1993 or 2006
Extrahierter Entscheid
The relevant benchmark was the original pension award of 30 September 1993, because the 2006 revision did not involve a substantive review of entitlement.
Extrahierte Begründung
Only a materially reviewed, legally correct prior decision can serve as the comparison point under Art. 17 ATSG; the 2006 file review was not such a decision.