I get that cascading part too then. (although my numbers are way too generous)
That scenario is were Mr. Hedge Fund realizes he can have something for nothing.
Mr Hedge Fund takes that hundred billion of 'protection' aka "risk" that he sold and bundles it up together as a synthetic CDS (sCDS). It has a bunch of tranches at a billion a piece:
<pre class="code"><table>
Seniority Quantity Basis Pts Paid Amt. Per Total Payment
1st 60 5 $500,000.00 $30,000,000.00
2nd 20 10 $1,000,000.00 $20,000,000.00
3rd 10 25 $2,500,000.00 $25,000,000.00
4th 4 35 $3,500,000.00 $14,000,000.00
5ht 3 40 $4,000,000.00 $12,000,000.00
6th 2 50 $5,000,000.00 $10,000,000.00
Last Eqt 1 2500 $250,000,000.00 $250,000,000.00
Total 100 $361,000,000.00
Profit $139,000,000.00
</table></pre>
Now Mr. Fund goes looking for a little protection of his own, for this sCDS. It's all an amalgam of that original AAA 'protection' he sold that has a 1% perceived default rate over five years. So Mr. Fund can make some money. Mr. Fund realizes that by bundling his risk up and creating seniority levels, just like 1st and 2nd mortgages, he can nearly eliminate the risk to the top tranches and thus, buy protection for them for nearly nothing.
For the 1st seniority tranche, he only needs to pay five basis points, a mere half a million dollars for a billion dollars of protection! He know it sounds nuts, but his old friend Mr. Bear Stearns says sure, I'd love to provide you that protection. It's five free basis points on a billion for me. The other six tranches have to fail before I don't get paid and that's a 40X expected default rate. I'll take all sixty!
Likewise down the line serious discounts to the orignal premium because we have to have way in excess the default before we pay out. Even down in the 3rd most senior tranche, we're paying 1/2 the premium rate for protection because they expect the default to be 1% and that means we need 10X the default rate before we even start to pay. And so on, to the 2nd to the last (6th most senior) and last seniority, the equity tranche.
For the 6th most senior, he can pay par on the premium because we need to exceed the default rate by about 100% before the provider has to pay, they are protected by the equity tranche, which expects to get wiped out but between the recovery rate and the fat 2500 basis point premium, expects to crank out fifty million dollars profit from their premiums over their expected pay outs of two hundred million a year and then suck up eighty million more in recovery. He sells that 6th tranche free money maker to his friend Buddy Hedge another billion dollar hedge fund.
Everybody is protected by the equity tranche, not only do the losses need to wipe out the tranche, but the losses have to exceed both the premiums and the recovery rate before the equity tranche has to pony up money. Roughly four hundred million in defaults per year before Mr. Equity Tranche feels a pinch becuase he's getting two hundred and fifty million in premiums, pulling in (40%) a 160 million in recoveries for $410MM. A touch over double the expected losses before the annual cash flow won't cover it.
Naturally, Mr. Hedge Fund will keep the equity tranche for himself, pocketing $389MM/yr, but he appears to only be exposed for two hundred million a year and he's got a billion, so he does it five times. Making 1.9 Billion in premiums and losing a Billion in protection payouts, but gaining an additional 400 Million in recoveries for a net 139% yearly profit. He takes his hundred and thirty nine million dollar bonus and feels like a god.
Until...
the defaults roll in at 3X and he doesn't have the money. He's short a billion... Then the ____ hits the fan. You see, Mr. Buddy Hedge, thought his risk was super small, and so did Moody's and everybody else, so he's holding a two hundred billion dollars of those 6th equity traches from a bunch of different people, two hundred in fact, and frankly, isn't expecting to pay out a bloody thing. Let alone one hundred million per tranche he's holding. He's short $18 billion dollars...
And the snowball is away...