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.
Builder's risk insurance insures against the risk of physical loss or damage to property during construction. Builder's risk insurance is typically written on an "all risk" basis covering damage arising from any cause (including the negligence of the insured) not otherwise expressly excluded. Builder's risk insurance is coverage that protects a person's or organization's insurable interest in materials, fixtures or equipment being used in the construction or renovation of a building or structure should those items sustain physical loss or damage from an insured peril.