Glossary Spotlight: Bornhuetter-Ferguson Technique

Definition: An actuarial method of forecasting losses, using loss development and loss ratio.

The Bornhuetter-Ferguson technique is a commonly used actuarial reserving method for estimating ultimate insurance losses. The method combines two key components: actual claims development and an expected loss assumption, often based on a selected loss ratio. Rather than relying entirely on reported or paid losses, the technique estimates the portion of losses that have not yet been reported or fully developed.

In practical terms, the Bornhuetter-Ferguson technique helps actuaries estimate how much an insurance program is ultimately expected to pay in claims. The method is often used when claims are still immature and early reported losses may not yet reflect the full cost of future claim activity. This is particularly relevant for long-tail lines of business such as workers compensation, general liability, medical professional liability, and other casualty coverages where claims may develop over many years.

The technique differs from methods that rely primarily on historical claims development patterns alone. For example, the chain ladder method projects future losses largely from actual reported or paid claims experience. The Bornhuetter-Ferguson technique instead combines actual claim emergence with an expected loss estimate for the portion of losses that remain unreported. As a result, the method can produce more stable reserve indications when claims data is limited or still developing.

A simplified example illustrates the concept. Assume a captive insurance company has $10 million in earned premium and an expected loss ratio of 60 percent, resulting in an expected ultimate loss estimate of $6 million. If actuarial analysis indicates that claims are currently estimated to be 40 percent reported, then 60 percent of the expected losses remain unreported. Under the Bornhuetter-Ferguson technique, the expected unreported losses would equal approximately $3.6 million, with actual reported losses incorporated into the overall reserve estimate.

For captive insurance companies, the Bornhuetter-Ferguson technique is commonly used in reserve analyses, actuarial opinions, feasibility studies, and annual financial reviews. Captive insurance programs may involve specialized risks, evolving exposures, or relatively limited historical claims data, particularly during early program years. In those situations, actuarial methods that depend entirely on historical development patterns may produce less reliable indications. The Bornhuetter-Ferguson technique can help balance actual claim activity with expected loss assumptions when evaluating reserve adequacy.

Actuaries typically evaluate the Bornhuetter-Ferguson technique alongside other reserving methods rather than relying on a single indication in isolation. The selected reserve estimate ultimately depends on factors such as claim maturity, reporting patterns, exposure changes, and the credibility of available historical data.

FAQs

Why is the Bornhuetter-Ferguson technique important in captive insurance?

Captive insurance companies often insure specialized risks or maintain smaller books of business than large commercial insurers. In some cases, historical claims data may be limited or claims may still be developing. The Bornhuetter-Ferguson technique can help actuaries estimate reserves by combining actual claim activity with expected loss assumptions rather than relying entirely on immature claims data.

When is the Bornhuetter-Ferguson technique most commonly used?

The technique is commonly used for immature accident years or long-tail casualty risks where claims may take years to fully develop. It is also frequently used in newer captive insurance programs, newly added coverage lines, or situations involving changing exposures where historical development patterns alone may not provide a fully credible indication of ultimate losses.

How does the Bornhuetter-Ferguson technique differ from the chain ladder method?

The chain ladder method primarily projects ultimate losses based on historical claims development patterns and actual reported or paid losses. The Bornhuetter-Ferguson technique instead combines actual claims emergence with expected loss assumptions for the portion of losses that remain unreported. This can help reduce volatility when claims data is still immature or less credible.