Secondary and tertiary accounts of the Toshiba-Kongsberg quieting effect's magnitude are mutually inconsistent, with no shared primary behind any of them

toshiba-kongsbergcold-warsubmarineexport-controlsverificationquant

Beyond the "50%" figure attributed to Rep. Duncan Hunter, other retellings of the Toshiba-Kongsberg sale's effect assert far larger — and mutually incompatible — magnitudes, with no citation overlap between them. GlobalSecurity.org states that "NATO antisubmarine warfare specialists could pick up the sounds of Soviet submarines from 200 miles away... after the Toshiba incident, the distance decreased to 10 miles" — roughly a 95% reduction, on an unsigned Tier-4 aggregator page. A King's College London "Project Alpha" case-study brief avoids a detection-range figure entirely, instead describing the propellers as made "twenty-fold quieter" and estimating total damage to the US Navy at "somewhere between $1 billion and $100 billion (1980s prices)" — a two-order-of-magnitude spread the brief itself calls "difficult to determine" (Tier 3, institutional but unsigned).

None of these figures — 50%, ~95%, "twenty-fold," or the $1B–$100B range — cites a shared underlying document, and no two of them are mutually consistent with each other or with the years-and-dollars framing in claim-csm-1987-dia-naval-intelligence-toshiba-assessment-years-dollars. Each individual figure is [unverified-quant — needs primary] on its own; the pattern across all of them — independently asserted, never reconciled — is itself the checkable finding here, sourced directly against each page's own text rather than resting on any single number.