但按比例计算，他们在国内收入中分享的比例下降了。
But proportionately, their share of national income has declined.
所产生的成本应根据展览者占用的面积按比例计算。
The costs incurred shall be determined on a prorata calculation of the area occupied by each exhibitor.
按比例计算的费用会用于手术费用，这样富裕的病人可以资助贫穷的病人。
A sliding scale of fees is used for operations so that richer customers subsidise poorer ones.
应用推荐