Inflation rates calculated using rates of change in the CPI and the GDP deflator are identical.

No, the inflation rates calculated using rates of change in the Consumer Price Index (CPI) and the GDP deflator are not identical. Here's why:

1. Different Basket of Goods: The CPI measures the price change of a specific basket of goods and services bought by households. The GDP deflator, on the other hand, measures the price change of all domestically produced goods and services in an economy. Therefore, they cover different sets of goods and services.

2. Different Weights: The CPI assigns fixed weights to the goods and services in its basket, reflecting their importance in the average household's budget. The GDP deflator assigns weights according to their share in the current year's GDP, which can change over time.

3. Substitution Bias: The CPI uses a fixed basket of goods and services, so it doesn't account for the fact that when the price of one good rises, consumers may substitute it with a cheaper alternative. The GDP deflator doesn't have this problem because it includes all goods and services produced.

4. Imported Goods: The CPI includes imported goods as they are part of the household's consumption, while the GDP deflator does not because they are not produced domestically.

So, due to these differences, the inflation rates calculated using the CPI and the GDP deflator can differ.