Widespread power outages and subway shutdowns may wind up making Superstorm Sandy the second most expensive storm in U.S. history. That would rank it right behind Hurricane Katrina. Eqecat said last week that the damage from the storm will likely be far worse than it previously predicted, largely a result of Sandy hitting the most densely populated area in the country. The firm doubled its previous estimate for the total bill and now says Sandy may have caused between $30 billion and $50 billion in economic losses, including property damage, lost business and extra living expenses. The cost to insurance companies could run as low as $10 billion and as high as $20 billion.