6.2
The Consumer Price Index, or CPI, measures how the average prices of goods and services change over time, specifically for urban consumers.
It’s based on a market basket that includes essentials like food, rent, clothing, transportation, healthcare, education, entertainment, and other goods and services. Each item is assigned a weight, depending on how much households typically spend on it. These weights come from national consumer expenditure surveys.
Although often called a “fixed” basket, the contents and weights are periodically updated to reflect real-world consumption patterns.
To calculate the CPI, statistical agencies choose a base year. The cost of the basket in the current year is then compared to its cost in the base year, using this formula.
The inflation rate is then calculated using the new and previous CPI figures.
The CPI helps adjust wages, pensions, and taxes, and serves as a key measure for tracking inflation.
However, CPI does not account for quality improvements or regional cost differences. Additionally, it doesn't account for substitution bias, which occurs when consumers switch to cheaper alternatives as prices rise.
Tracking changes in the cost of living is central to economic planning and policy. The Consumer Price Index (CPI) is one of the most widely used tools…
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