According to the French legal system, the value of $7 billion is 3 years in jail. That's what Jerome Kerviel got for fraudulent trading which saddled Societe Generale with a $7 billion loss.
EPA's economic analysis estimates the value of a US human life at about $7 million.
The reason a life can be assigned a value is because it takes a certain amount of money in order to save a US life. If you have $14 million, you could use that in the US to save, most efficiently, about 2 human lives total. Or that's what EPA suggests.
The money wasted by Jerome Kerviel could, therefore, have been used to save 1,000 human lives.
So basically he wasted 1,000 human lives worth of money, and what he gets is 3 years in jail.
Of course the damage cannot be undone, regardless of whether the jail time is 3 years, or a lifetime, or if he is simply executed, like the Chinese would have done.
But money is about human lives. Economic damage is about human lives. A system which handles this sort of wrongdoing by, basically, giving the guy a slap on the wrist, does not have its priorities straight.