This is an accounting term and refers to the premiums that are entered in the books of either an insurer or a reinsurer when a policy is issued and eventually paid for. It may include direct (written by the insurer's subsidiaries for all policies) and assumed (received from an authorized state mandated pool) premiums written. Breaking down the concept, they determine the overall amount that consumers are willing to pay for insurance plans/ policies that were sold to them in the specific accounting period. Experts believe that these are the key source of an insurance corporation's revenues. Consequently, they get the top spot in the income statement of these corporations.