Cost of Living Index – The cost of living index is a number that compares how affordable it is to live in one area versus the national average, which is set at 100. If the index is below 100, the area is more affordable than average. If it’s above 100, it’s more expensive to live there. For example, the HRTX region has a cost of living index of 93.4, meaning it’s 6.6% cheaper to live here compared to the U.S. average. That means your paycheck can go further!