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From 1949 to the early 1970s, China was almost a self-sufficient economy, and invested little in transportation infrastructure. “Ihe average invesmaent in transpotation was about 3 percent of ttxal investment (China Statistical Yearbook 1991, 133). “Ihe kilometers of rail tracks barely doubled, the amount of Oared reads increased by only 1.3 times and only thirty new port berths were built. Conversely, freight volumes grew by 21, 34, and 31 times in rail, motor, and waterway, 相似文献
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