W & gtm，所以取W為計費噸。
運費=(0.04 * 500 * 100)*(1+20%+10%)
= $2,600
損益=外匯凈收入*外匯牌價-出口總成本
= (60 * 500-2600) * (817/100)-200,000
=23858元
盈虧率=盈虧額/出口總成本*100%
= 23858/200,000 *100%
=11.929%