Aggregate price level

The general price level is a hypothetical daily measure of overall prices for some set of goods and services (the consumer basket), in an economy or monetary union during a given interval (generally one day), normalized relative to some base set. Typically, the general price level is approximated with a daily price index, normally the Daily CPI. The general price level can change more than once per day during hyperinflation.

The classical dichotomy is the assumption that there is a relatively clean distinction between overall increases or decreases in prices and underlying, “nominal” economic variables. Thus, if prices overall increase or decrease, it is assumed that this change can be decomposed as follows:

Given a set ${\displaystyle C}$ of goods and services, the total value of transactions in ${\displaystyle C}$ at time ${\displaystyle t}$ is

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