(In thousands) December 31, 2018 Loss reserve discount: Other liability $ — Primary workers' compensation — Excess workers' compensation (434,302) Professional liability — Commercial automobile — Short-tail lines — Other — Insurance (434,302 ) Casualty (128,790) Property — Reinsurance (128,790) Total loss reserve discount $ (563,092 ) Total gross reserves for loss and loss expenses $ 11,966,448 The following is supplementary information regarding average historical claims duration as of December 31, 2018: Insurance Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance Years 1 2 3 4 5 6 7 8 9 10 Other liability 8.0 % 14.4 % 18.4 % 16.8 % 13.8 % 8.2 % 5.9 % 3.0 % 2.8 % 1.8 % Primary workers' compensation 22.5% 27.6% 15.6% 9.4% 5.9% 4.0% 2.8% 1.9% 1.6% 1.1% Excess workers' compensation 3.8 % 3.3 % 2.7 % 3.1 % 3.0 % 3.3 % 2.7 % 3.3 % 3.5 % 2.6 % Professional liability 8.7% 22.7% 22.3% 16.6% 9.4% 9.1% 3.5% 1.6% 4.3% 2.5% Commercial automobile 39.7 % 21.6 % 15.6 % 10.7 % 6.8 % 3.5 % 1.0 % 0.4 % 0.2 % — % Short-tail lines 59.6% 29.8% 5.8% 1.6% 0.1% 0.3% 0.4% 0.3% —% 1.4% Reinsurance Average Annual Percentage Payout of Incurred Claims by Age, Net of Reinsurance Years 1 2 3 4 5 6 7 8 9 10 Casualty 7.2 % 12.5 % 14.6 % 13.3 % 11.2 % 9.0 % 5.9 % 5.2 % 3.8 % 2.8 % Property 35.3% 32.3% 14.8% 5.5% 3.9% 2.0% 3.2% 2.7% —% 3.2% 88