Embodiments for determining a traded item's value are described herein. An embodiment includes identifying conditions for use in computing a value of the tradable object. The embodiment further includes determining whether a condition is satisfied based on market data, for example, and if the condition is satisfied, then determining the value of the item based on a rule associated with the condition; and if the condition is not satisfied, then determining whether a subsequent condition is satisfied. If a subsequent condition is satisfied, then determining the value of the tradable object based on a rule associated with the subsequent condition. An embodiment further includes computing an open profit and loss value based on the item's value. Other embodiments are also disclosed.