Rating Variables: What They Are and Why They Matter

Accident History. Gender. Marital Status. Credit Score. What do these things have in common? They are all rating variables that an actuary might use to calculate your insurance premiums.

The use of rating variables by actuaries and insurance companies is getting increased focus in state and federal legislative groups as well as in the media. But what are rating variables exactly, and how are they used by actuaries? The CAS and Insurance Information Institute (I.I.I.) published a white paper last month to help educate consumers and policymakers on the topic, and we thought students studying to be actuaries would be interested in the paper as well.

Rating variables are the characteristics of consumers that can help approximate the cost of their risks. For example, the make, model, or mileage of your car factor into how much you pay for your auto insurance – we also created this handy infographic to illustrate this concept. However, when one or more rating variables, such as gender or credit score, is removed from the equation (which can happen through legislation at the state level), there can be unintended consequences. The new white paper seeks to explain some of the potential outcomes that can occur when rating variables are restricted.

There is certainly evidence of variable restrictions in various states: California recently passed a law banning gender rating, and law changes in Michigan will restrict the use of many rating variables such as credit score and geographic zip code. James Lynch, FCAS, of the I.I.I. recently represented the insurance industry, and the actuarial profession, at a congressional hearing regarding rating variables and discrimination (fast forward to 36:04 to watch Jim’s testimony). As the issue of rating variables evolves in the eyes of legislators and the public, the CAS/I.I.I. white paper will continue to serve as a resource to help with the understanding of why rating variables help make insurance both fair and affordable.

If you are interested in learning more about the basics of rating variables, we encourage you to read the white paper and share with others! As you continue your path to becoming a P&C actuary, keep in mind that actuaries can serve an important role in explaining the concepts and calculations that go into the “behind the scenes” work that ultimately affects every consumer carrying insurance.