Business sense / Berkshire Hathaway
Float has a cost and a claims calendar.
Underwriting results determine whether float is cheap or costly; investment income is a separate return.
How the choices connect
- 01
Collect premiums
Cash arrives before many claims are paid.
- 02
Reserve obligations
Future claims remain a real liability.
- 03
Invest prudently
Assets must match liquidity needs and risk.
- 04
Pay claims
Severity and timing can change the funding value.
The economic question
A growing float balance is not automatically a growing economic benefit. Underwriting losses can consume investment return. The balance sheet also needs enough liquid assets to pay claims when due, including adverse outcomes.
What to investigate
Stress claim severity and payment acceleration separately, then test asset liquidity. The simple annual exercise below assumes average float and investment yield; it omits taxes, discounting and capital requirements.
Separate the fact from the inference
Reported · historical snapshot
Berkshire reported approximately $171 billion of insurance float at year-end 2024. Its annual report measures the cost of float using underwriting earnings or losses relative to average float.
Berkshire Hathaway FY2024 annual report · Insurance float ↗Reporting period is stated above; this is not a live financial feed.
Method · Harper analysis
Separate underwriting results from investment income. Model when premiums arrive and claims are paid, then compare investment returns with underwriting losses and the liquidity needed for adverse claims.
A falsifying check
Stress claim severity and payment timing. Float is not shareholder equity or permanently free funding; unfavorable underwriting can make it expensive.
Would you accept faster premium growth if underwriting losses also rise? Calculate the cost of the additional float before counting the investment income it could earn.
Original case lab · illustrative, not company results
Can investment income cover underwriting losses?
Synthetic insurer: $100m average float; 4% annual investment return; underwriting loss variable. Illustrative claim payments: $20m, $30m, $50m over three periods, with no new premium inflow in the timeline.
Range 0–12. Enter an exact value or use the slider.
Temporary scenario · reset on reload.
Cost of float = underwriting loss ÷ $100m. Net before other costs = $4m investment income − underwriting loss.
At a $4m underwriting loss, cost of float equals the 4% investment return. Claims still require cash even when accounting returns look positive.
Carry the method into a complete fictional case. The Studio exercise practices a related skill; it does not simulate Berkshire Hathaway.
Open related Case Studio practice →Read the framework →