However it would be equally false to believe that the only useful data point come from future market. Every market that enable trade gambling is bound to be vo

However it would be equally false to believe that the only useful data point come from future market. Every market that enable trade gambling is bound to be volatile and sometimes disconnected from reality. Gamblers that manage to to accurately estimate this delta are the winning one. PS: Actually that's how you end up with negative price, a gambler acquired a huge quantity of gaz in the future market hoping to sell it even higher on the daily market. Nice weather daily market drop. He end up selling negative because he's just a gambler living in NYC and he don't have any usage for the gaz he own in a ship ready to deliver in the European northern sea. So he is ready to pay to get away of this deal and soon enough he is ready for his next sad gamble...