What Price Should BP Valued at with the Horrible Spill Still Evolving

Some rough estimates might be good to figure out whether it is better to Sell or Hold.   The BP/RIG accident outcome could be identified based on the EXXON Valdez event. There I believe $5B was the payout. Carried with 4% inflation out 22 years would yield say a new cost of litigation at 12Billion if the Exxon accident is accurate. Seems like BP has lost about 20% of its stock price already which would be about $31B loss. Do you think the market might be overreacting just a little?   I would say to over reaction on the above would be close to about 10points on the stock reduction in BP if the Exxon/Valdez disaster is an accurate model.    Anybody have another model that might prove better?