The Market Value associated with an Open Position is the current value of that position at the current market price for that market. Market price is defined as (Best Bid + Best Offer) / 2, so if best bid for a market is $48 and best offer is $52, the Market Price is $50. For a Bought Position, the Market Value is always positive, while for a Sold Position, the Market Value is always negative.
Market Value
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