1. Up to 2000 losses of unknown size, yet balancing of books perfectly legal
2. Annual Report 2001 (google for it, still online at olympus):
Marketable securities 36.483 bn yen
Investment securities 102.598 bn yen
Losses must be hidden in these positions, so max. 100% loss 139.081 bn yen
So Olympus will have to restate 2001 with extraordinary loss of up to additional 139.081 bn yen.
That's all there is in negative corrections.
Then just undo the fake takeovers of Altis, Humalabo, News Chef. 73.4 bn yen, probably 80% of the amounts were fake. So ca 58.7 bn more cash flow between 2006-2008
Undo the 80% writeoff as those amounts were fake. So 58.7 bn more earnings in 2008.
Undo the $687 mio fake payment to axes/axam in 2009. Let's assume $650 were fake. So $650 mio more cash flow in 2009. No goodwill position for that $650 mio (52 bn yen). No need to write off the goodwill position as it came to the balance sheet only due to the fake accounting.
Adapt everything for tax implications and the balance sheets for every year and everything is clean.
Oh I forgot one thing: you also have to revert the sale of the securities. Olympus must have done a fake sell of the worthless securities at 139.081 bn. If written off in 2001 you can't sell them anymore.
It's all there in the annual reports of 2001-2011.
In the end there are up to 139.081 bn yen losses previously unknown to shareholders. Yet there are 58.7bn more earnings in 2008. And 52 bn yen less goodwill to be written off, so 52 bn yen more future earnings.
Without considering tax implications the net "surprise" loss previously unknown to shareholders is max. below 40 bn yen.