The term bonus–malus (Latin for 'good-bad') is used for a number of business arrangements which alternately reward (bonus) or penalize (malus). It is used, for example, in the call center and insurance industries. Call centers In call centers, a bonus–malus arrangement is a section in the contract between the company buying the call center services (buyer) and the company providing the call center services (call center) allowing for a payment to be made from one company to the other. As part of the contract, both companies agree on a set of Key Performance Indicators (KPIs). These are measurements for how the call center is performing. If the call center is performing poorly, then there would be a malus payment (payment from the call center company to the buyer). If the call center is doing well, then there is a bonus payment from the buyer to the call center company. Bonus–malus payments are in addition to the normal cost of call center services. Insurance In insurance, a bonus–malus system (BMS) is a system that adjusts the premium paid by a customer according to their individual claim history. Bonus usually is a discount in the premium which is given on the renewal of the policy if no claim is made in the previous year. Malus is an increase in the premium if there is a claim in the previous year. Bonus–malus systems are very common in vehicle insurance. This system is also called a no-claim discount (NCD) or no-claims bonus in Britain and Australia. The fundamental principle of BMS is that the higher the claim frequency of a policyholder, the higher the insurance costs that on average are charged to the policyholder. This principle is also valid in an insurance arrangement consisting of a high maximum deductible which is common to all policyholders. Automobile insurance Most insurers around the world have introduced some form of merit-rating in automobile third party liability insurance. Such systems penalize at-fault accidents by premium surcharges and reward claim-free years by discounts, commonly known as a "no-claims discount". The most usual BMS divides drivers by classes, where each class has its own discount or surcharge that is applied to the basic premium. A claim-free year implies in a decline of one or more degrees on the Bonus/Malus class table on the anniversary of the contract. A claim entails an increase of a given number of degrees on the