Sounds catchy but fortunately thats not quite the case. Swiss Banks must keep 125% of deposits in assets. If you deposit 100 CHF, they must have e.g. mortgages worth 125 CHF.
These assets may not be liquid and they may be booked to maturity. Meaning that interest rate risks were not reflected yet. So in a bank run, the Bank may find itself in a situation where they can only sell these assets for lets say CHF 120. In such situation, the Bank took a hit of 5 on its balance sheet.
If, a Bank operated at a hard cash coverage ratio of 10%, the Bank would post a Bank run return pay all deposits back and it would face a reduction in its equity of 50%.
If the Bank‘s equity detoriated too low and it went into a resolution case, additional bail-in bonds would be triggered (which was not the case at CS, they only triggered their AT-1). These bail-in bonds would further increase the Bank‘s equity and therefore provide additional moneys to pay back the deposits.
If we post this STILL face missing cash, the deposit insurance jumps in to pay the missing Delta (up to the stated amount). So the 8k you calculated is only relevant for that additional piece of cash.
A simplistic calculation:
- Deposit of 100
- Mandatory Assets of 125
- Asset Value / Resolution Loss of 20% => Bank is at zero Equity (before bail-in amount) yet you get 100% of your deposit back (and deposit insurance doesnt pay a thing)
- Asset Value / Resolution of ~ 25% => Bank is at zero Equity and Bail-in Amounts are consumed; you still get your deposit and insurance doesnt pay a penny. Bank and additional bail-in bonds are dust.
- Asset Value / Resulution at ~ 33% => Now we have another 8 of loss, which equates to max insurance amount of the deposit insurance you calculated for a worst case, mass bank colapse; you still get all your deposit back but the insurance is at its limit
Conclusion - the banks‘ assets would need to materially lose value before the deposit insurance gets into trouble. And even then, a scenario where you take a material hit is pretty much unthinkable.
This is of course always dependant on no fraud, no mis-valuation and no complete illiquidity and no shock interest increase (steady ones are less of a Problem and just lead to timely resolution before deposits were at risk). GFC was a special case here as banks sat on toxic assets that truly became illiquid. Banks books by now look way more traditional. Unless we have an over-night interest hike of 10% percent, I don‘t see Swiss deposits at risk, even at the former CS.
Clearly, the situation is different with non-deposit liabilities the Bank had e.g. ETN‘s.