“运输量”的英语？

火车货运的 运输量 继续减少.Freight - car loadings continue to slack off.河运延误的情况在一定程度上因运输量下降而减少.Delays on the are declining partly due to less traffic.据估计,从现在起到2020年, 航空运输量将增加2倍.According to estimation arrive from now on 2020, aviati...