For open-end credit transactions, the rating plan of the insurer must address, by the grouping of similar accounts, the expected variance in the ratio of goods purchased that are covered under the credit personal property insurance and goods that are not covered by that insurance. Accounts must be separated into groups that have or are expected to have a similar ratio of goods purchased that are covered under the credit personal property insurance and goods that are not covered by that insurance.
NRS 691C.360