What is the purpose of the Consumer Price Index?
It’s one way of measuring the rate of inflation. The Consumer Price Index is calculated by the Bureau of Labor Statistics, and is the subject of controversy. Some think it understates inflation. Others think it overstates inflation. Whatever its flaws, it’s probably the most commonly used measure of inflation. You can counteract the impact of inflation on your retirement savings (at least to a large degree) by increasing the amount you save by the rate of inflation.