In: Economics
GDP Deflator is generally considered to be a better measure for inflation calculation, there are multiple reasons for that first being GDP Deflator takes into account the price change of all the goods originating from the economy while CPI only takes a basket as price measure, having all goods solve problem of substitution which we have in basket since as price increase people shift to substitute product and this is not dynamically captured in price basket,also consumption change because of technological advancement like higher service life of products and all which affects the CPI basket price is captured completely with the GDP Deflator. Further GDP Deflator capture the price change of all the product and volume of production solves the issue of correct weight in baskets as we have the issue with CPI as a inflation measure tool. Issue with GDP Deflator that it does not take into account the price changes of imports is generally marginalised since the imported product price will tend to move in accordance to domestic produce otherwise those products won't be competitive in the domestic market, further these products generally have small weightage in the CPI too. So, Overall GDP Deflator appears to be more accurate tool for inflation calculation within national boundary.