单向双向：某些产品的手续费只在开仓时收取，有些则在开仓和平仓时都收取； The System for each income metric over the revenue and loss statement (P&L) is stated in the next listing: This method calculates the value of the trade based on the current and the prior day's price ranges. The method for rate impression using the revaluation system is La PNL waiting for link from Social Network Posts (72)