the contract can vary as a function of supply and demand, causing one side of the exchange to lose money at the expense of the other.

To mitigate the risk of default, the product is marked to market on a daily basis where the difference between the initial agreed-upon price and the actual daily futures price is re-evaluated daily. This is sometimes known as the variation margin, where the futures exchange will draw money out of the losing party's margin account and put it into that of the other party, ensuring the correct loss or profit