The NAIC auto insurance database and its lag

What the report is

The NAIC is the standard-setting body of the state insurance commissioners. Its auto insurance database report gathers written premium and written exposure data reported by insurers across every state and publishes state-level summaries from them. It is the only auto premium dataset in the country assembled on a single consistent basis, which is exactly why it is cited so heavily.

It is also expressly republication-restricted. The report’s front matter reserves all rights and prohibits reproduction, storage in a retrieval system, or transmission in any form without written permission. Free to download is not the same as free to republish, and this site therefore treats the report as citable context on this page alone rather than as a data source. No figure from it appears on any other page, and none of the premium distributions on this site derives from it.

The two metrics, restated

The report’s headline measures are easy to confuse and mean different things. Written in our own words rather than the report’s: the first divides the total premium written for liability, collision and comprehensive combined by the count of liability exposures, so it describes what an average insured vehicle costs across all the coverages actually bought, including vehicles carrying no collision or comprehensive cover at all.

The second adds together the separate average premium for each of the three coverages, so it describes a vehicle that carries all three. The two therefore answer different questions and cannot be swapped for one another, and a figure quoted without naming which one it is cannot be interpreted.

Neither is a measure of what a defined driver pays for a defined coverage package in a defined place. Both are quotients of aggregates, which is the root of the caution the report prints about itself.

The lag

The edition current at the time of writing was adopted in December 2025 and released in February 2026, carrying data for calendar year 2023. That is roughly a two-year gap between the market being described and the description being available. The companion average premium supplement runs shorter but is still measured in many months rather than weeks.

A gap of that size is fatal for a market that has moved. The federal price index for motor vehicle insurance carries a reading for June 2026 showing a twelve-month change of −4.1%, while the national database describes a period that ended years earlier. Both can be accurate about their own moment; only one of them is about now.

That is why this site builds its trend layer on the monthly price index and its premium layer on state regulator surveys, the newest of which carries rates effective August 2026, in Maryland. Neither layer needs the national aggregate, and neither reproduces it.

The caution the report prints about itself

The report explains that its calculations make no distinction as to policyholder classifications, vehicle characteristics, or the selection of specific limits or deductibles, and then adds its own warning in capitals: “direct comparisons between state results should be treated with a high degree of caution.”

That instruction is the opposite of how the dataset is generally used. Ranking states from most to least expensive is precisely the comparison the compiler cautions against, because a state whose drivers buy higher limits and more collision coverage will look more expensive than a state whose drivers buy less, entirely regardless of price.

The alternative this site takes is narrower and slower. It publishes 13 states’ regulator surveys as separate, individually dated distributions and refuses to rank the 51 jurisdictions against each other on premium at all.

Questions

Why does this site not use the NAIC database for state figures?

Three reasons, each sufficient on its own: the report prohibits reproduction without written permission, it publishes data roughly two years after the year it describes, and it cautions against comparing state results, which is the only use a state-by-state page would make of it.

How out of date is the current edition?

The edition current at the time of writing was adopted in December 2025 and released in February 2026 carrying calendar year 2023 data. The price index this site tracks carries a reading for June 2026.

What does this site publish instead?

Distributions computed from the surveys published by 13 state regulators, each dated to its own source and never merged across states, plus the federal price index for direction over time.