Short Story Insurance Lets now look at Berkshires various businesses, starting with our most important sector, insurance. The property/casualty (P/C) branch of that industry has been the engine that has propelled our growth since 1967, the year we acquired National Indemnity and its sister company, National Fire & Marine, for $8.6 million. Today, National Indemnity is the largest property/casualty company in the world as measured by net worth.

One reason we were attracted to the P/C business was its financial characteristics: P/C insurers receive premiums upfront and pay claims later. In extreme cases, such as claims arising from exposure to asbestos, payments can stretch over many decades. This collect-now, pay-later model leaves P/C companies holding large sums money we call float that will eventually go to others. Meanwhile, insurers get to invest this float for their own benefit. Though individual policies and claims come and go, the amount of float an insurer holds usually remains fairly stable in relation to premium volume. We recently wrote a huge policy that increased float to more than $100 billion. Beyond that one-time boost, float at GEICO and several of our specialized operations is almost certain to grow at a good clip. National Indemnitys reinsurance division, however, is party to a number of large run-off contracts whose float is certain to drift downward.

We may in time experience a decline in float. If so, the decline will be very gradual at the outside no more than 3% in any year. The nature of our insurance contracts is such that we can never be subject to immediate or near-term demands for sums that are of significance to our cash resources. This structure is by design and is a key component in the unequaled financial strength of our insurance companies. It will never be compromised.

If our premiums exceed the total of our expenses and eventual losses, our insurance operation registers an underwriting profit that adds to the investment income the float produces. When such a profit is earned, we enjoy the use of free money and, better yet, get paid for holding it.

Unfortunately, the wish of all insurers to achieve this happy result creates intense competition, so vigorous indeed that it sometimes causes the P/C industry as a whole to operate at a significant underwriting loss. This loss, in effect, is what the industry pays to hold its float. Competitive dynamics almost guarantee that the insurance industry, despite the float income all its companies enjoy, will continue its dismal record of earning subnormal returns on tangible net worth as compared to other American businesses. Question: Describe what Buffett means by float and underwriting profit in his overview of Berkshires insurance business.