Reserve Development and the 'Underlying' Combined Ratio
Atlas Casualty reports 2024 earned premium of $300 million, incurred losses of $180 million, and underwriting expenses of $75 million. Incurred losses include $30 million of adverse prior-year development in general liability, partly offset by $10 million of favorable auto development, for $20 million net adverse development. The CFO presents an 'underlying' loss ratio that excludes all development and calls the 85% calendar-year combined ratio misleading. Separately, the actuary's central estimate of net carried reserves is $660 million versus $620 million booked; the actuarial range is $640 million to $700 million. The CFO says no strengthening is needed because the booked amount is within the range.
1. Compute the calendar-year and accident-year loss and combined ratios, showing the formulas.
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Calendar-year loss ratio = $180 million / $300 million = 60.0%. Expense ratio = $75 million / $300 million = 25.0%. Calendar-year combined ratio = 60.0% + 25.0% = 85.0%. Accident-year loss ratio, excluding the $20 million net prior-year development, = ($180 million - $20 million) / $300 million = $160 million / $300 million = 53.3%. Accident-year combined ratio = 53.3% + 25.0% = 78.3%. The 6.7-point difference is the net effect of prior-year reserve development. If the analysis separates liability adverse development from auto favorable development, the liability accident-year loss ratio is ($180 million - $30 million) / $300 million = 50.0%, while the auto favorable development flatters the all-lines accident-year ratio. The all-lines accident-year figure therefore mixes two different reserve signals and should be read with the components disclosed.
2. Is the CFO's 'underlying' combined ratio appropriate? Explain what it conceals.
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It can be appropriate as a supplemental non-GAAP measure if clearly defined, reconciled to the GAAP combined ratio, and not presented as the primary result. It is not appropriate to call the 85% calendar-year ratio misleading while implying that 78.3% is the true performance. Prior-year development is a real economic cost and is evidence about the adequacy of earlier estimates. Excluding all development conceals that the liability line needed $30 million of strengthening and that current capital is absorbing prior estimation error. Netting favorable auto development against adverse liability development also obscures the fact that the auto reserves may have been redundant while liability reserves were deficient. The reconciliation should show the $20 million net development, its 6.7-point effect, and the gross components. Investors and regulators should be able to see both the accident-year result and the cumulative development trend.
3. Evaluate the reserve adequacy conclusion and compute the pro forma combined ratio if the central estimate is booked.
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The conclusion is not supportable. A range is not a menu of acceptable balance sheet amounts; the recorded reserve should be the actuary's best estimate, here $660 million. Carrying $620 million leaves a $40 million deficiency, even though $620 million falls inside the $640 million to $700 million range. In fact, $620 million is below the low end of the stated range, which makes the CFO's argument internally inconsistent. Booking the $40 million strengthening increases incurred losses from $180 million to $220 million. The pro forma loss ratio becomes $220 million / $300 million = 73.3%, and the combined ratio becomes 73.3% + 25.0% = 98.3%. The company should disclose the strengthening, the change in estimate, and the effect on surplus and RBC. If the $40 million is material, the audit committee should review the process that allowed a below-range reserve to be carried.