Insurance policies can be complex and some policyholders may not understand all the fees and coverages included in a policy. As a result, people may buy policies on unfavorable terms. In response to these issues, many countries have enacted detailed statutory and regulatory regimes governing every aspect of the insurance business, including minimum standards for policies and the ways in which they may be advertised and sold.
At the most basic level, initial ratemaking involves looking at the frequency and severity of insured perils and the expected average payout resulting from these perils. Thereafter an insurance company will collect historical loss data, bring the loss data to present value, and compare these prior losses to the premium collected in order to assess rate adequacy. Loss ratios and expense loads are also used. Rating for different risk characteristics involves at the most basic level comparing the losses with "loss relativities"—a policy with twice as many losses would therefore be charged twice as much. More complex multivariate analyses are sometimes used when multiple characteristics are involved and a univariate analysis could produce confounded results. Other statistical methods may be used in assessing the probability of future losses.
A history of chronic disease or other potential health issues with an individual or family, such as heart disease or cancer, may result in paying higher premiums. Obesity, alcohol consumption, or smoking can affect rates as well. An applicant typically goes through a medical exam to determine whether he has high blood pressure or other signs of potential health issues that may result in premature death for the applicant and increased risk for the insurance company. People in good health typically pay lower life insurance premiums.