By Dr. Steven Weisbart, Chief Economist, Insurance Information Institute
There are remarkable good news on the auto insurance front – auto insurance prices have been downward since February 2018, and are now below the general inflation rate, but no one seems to have noticed
The vast majority of consumers in America buy auto insurance, so the Bureau of Labor Statistics calculates a price component for each part of the various versions of the Consumer Price Index (CPI). 
But insurance, like many products and services, is a difficult product for which to calculate a price. Ideally, one would like to change only the amount that would be paid to buy the exact same thing today as he / she would have paid in a prior time period. The challenge, with auto insurance as with many other products, is matching "the exact same thing" from a prior period. With cars, BLS tries to remove the effect in price changes of changes in features in different models that differ from prior models. period. Obviously, changes can also be affected by expected investment results and by expense issues such as reinsurance prices. BLS has no way to account for these effects. It does try to standardize its calculation by using a hypothetical group of policyholders applying for a specified set of coverages and asking for a panel of insurers to provide quotes for them
So when, in 201
The peak price change reached 9.7 percent in February 2018. But the spike in frequency ended, and you can see in figure 1 that year-over-year price changes for auto insurance started trending down, ending the year at an increase rate of 4.7 percent.
The downward trend has continued into 2019. Figure 2 shows the results through April:
BLS says that the April 2019 auto insurance price is only 1.4 percent above the price in April 2018. This is not only below the rate of general inflation which, depending on how you measure it, has been running at roughly 2 percent for several years, but it is also the lowest year-over-year increase in car insurance prices in over a decade (the last time the rate of increase was this low was in March 2008 – ie 1.4 percent.
So where are the headlines?
 The most common index is the Consumer Price Index for All Urban Consumers (CPI-U) —prices as experienced by all urban consumers, but BLS also publish CPI-W (prices as experienced by urban wage earners and clerical workers).