Often a commercial insured's liability insurance program consists of several layers. The first layer of insurance generally consists of primary insurance, which provides first dollar indemnity for judgments and settlements up to the limits of liability of the primary policy. Generally, primary insurance is subject to a deductible and obligates the insured to defend the insured against lawsuits, which is normally accomplished by assigning counsel to defend the insured. In many instances, a commercial insured may elect to self-insure. Above the primary insurance or self-insured retention, the insured may have one or more layers of excess insurance to provide coverage additional limits of indemnity protection. There are a variety of types of excess insurance, including "stand-alone" excess policies (policies that contain their own terms, conditions, and exclusions), "follow form" excess insurance (policies that follow the terms of the underlying policy except as specifically provided), and "umbrella" insurance policies (excess insurance that in some circumstances could provide coverage that is broader than the underlying insurance).[36]
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.[24] 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.
Crop insurance may be purchased by farmers to reduce or manage various risks associated with growing crops. Such risks include crop loss or damage caused by weather, hail, drought, frost damage, insects, or disease.[33] Index-based insurance uses models of how climate extremes affect crop production to define certain climate triggers that if surpassed have high probabilities of causing substantial crop loss. When harvest losses occur associated with exceeding the climate trigger threshold, the index-insured farmer is entitled to a compensation payment.[34]
Large loss: The size of the loss must be meaningful from the perspective of the insured. Insurance premiums need to cover both the expected cost of losses, plus the cost of issuing and administering the policy, adjusting losses, and supplying the capital needed to reasonably assure that the insurer will be able to pay claims. For small losses, these latter costs may be several times the size of the expected cost of losses. There is hardly any point in paying such costs unless the protection offered has real value to a buyer.

An insurance underwriter's job is to evaluate a given risk as to the likelihood that a loss will occur. Any factor that causes a greater likelihood of loss should theoretically be charged a higher rate. This basic principle of insurance must be followed if insurance companies are to remain solvent.[citation needed] Thus, "discrimination" against (i.e., negative differential treatment of) potential insureds in the risk evaluation and premium-setting process is a necessary by-product of the fundamentals of insurance underwriting.[citation needed] For instance, insurers charge older people significantly higher premiums than they charge younger people for term life insurance. Older people are thus treated differently from younger people (i.e., a distinction is made, discrimination occurs). The rationale for the differential treatment goes to the heart of the risk a life insurer takes: Old people are likely to die sooner than young people, so the risk of loss (the insured's death) is greater in any given period of time and therefore the risk premium must be higher to cover the greater risk.[citation needed] However, treating insureds differently when there is no actuarially sound reason for doing so is unlawful discrimination.
Terrorism insurance provides protection against any loss or damage caused by terrorist activities. In the United States in the wake of 9/11, the Terrorism Risk Insurance Act 2002 (TRIA) set up a federal program providing a transparent system of shared public and private compensation for insured losses resulting from acts of terrorism. The program was extended until the end of 2014 by the Terrorism Risk Insurance Program Reauthorization Act 2007 (TRIPRA).
One of the best ways to get cheap car insurance is by comparing car insurance quotes — and the companies offering them. To get you started, NerdWallet looked at car insurance prices across the country for different driver profiles and coverage levels to find the cheapest rates. We’ve sliced the data in several ways to give you an idea of average costs and what factors might nudge your car insurance rate up — or even better, down.
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