The $600B-$1.5T figure was a total of securitizations over many years, many of which have already been closed hence there would be no retained interests left. The $24B-$27B figure was the actual market value of the assets in June 2008, it wasn't 3% of that figure. I can only rely on figures that were supported by documentation which is $24B-$27B. We also don't know exactly how much retained interests WAMU held in their securitizations or if it was done for every Trust formed.
NOTE: Retained Interests in securitizations have to be reported in the books/filings, unlike Securitized loans which are off-balance and not recorded.
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