If the government intervenes by implementing, for example, a tax or a subsidy, then the graph
ol supply and demand becomes more complicated and will also include an area that
represents government surplus. Combined, the consumer surplus, the producer surplus, and
the government surplus (if present) make up the social surplus or the total surplus. Total
surplus is the primary measure used in welfare economics to evaluate the efficiency of a
A basic technique of bargaining for both parties is to pretend that their surplus is less than it
really is: sellers may argue that the price they ask hardly leaves them any profit, while
customers may play down how eager they are to have the article.
In some schools of thought, the economic surplus denotes the total income which the ruling
class derives from its ownership of scarce factors of production, which is either reinvested or
spent on consumption.