The chart shows the outcomes (vertical axis) for depositors in banks in Cyprus based on size of deposit (horizontal axis). We've done the story just up to 250,000 euro but everything is linear beyond that. The green line on the top is what would happen if these were solvent banks -- everyone gets their money back one for one. The blue line is what happens under the levy -- there's a slight kink at 100,000 euro since the levy is higher above this point. The red line is what would happen if the banks were put into insolvency, since they are insolvent by virtue of having invested in Greek government bonds.
Key point about insolvency: any depositor under 100,000 gets all their money back through deposit insurance. We've assumed that depositors over 100,000 recover half of the amount over 100,000 from the carcass of the busted bank. The gap between the blue line and the red line is how much the big money depositors gain from paying a percentage levy rather than seeking to recover from a dead bank.