There are two main methods in transmission service pricing at present , i. e. the accounting based embedded cost method and the economics based marginal cost method.

目前所提出的输电定价方法主要分为基于会计学的综合成本法和基于微观经济学的边际成本法。

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The company should already be charging the most it can for that marginal phone call and a change in sunk costs might affect accounting profit but not that revenue maximising price charged.

FORBES: India's Mobile Phone Operators Insist It's Not a Competitive Market