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 formulation for each gain metric about the income and decline statement (P&L) is said in the subsequent record:"hitparade.ch - Discographie PNL". Hung Medien. Retrieved 26 September 2016. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z