It is about the marginal propensity to consume (MPC), which is the extra consumption generated by a dollar of extra income.

而是与边际消费倾向(MPC)有关，即收入每增加一美元带来的相应消费增量。

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Farmer's income increases slowly and unsteadily in China. That has caused farmers' marginal propensity of low and insufficient consumption.

我国农民收入增长缓慢且不稳定，致使农民边际消费倾向偏低，消费总量不足。

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