Unum US Group Life and Accidental Death and Dismemberment Operating Results Shown below are financial results and key performance indicators for Unum US group life and accidental death and dismemberment. (in millions of dollars, except ratios) Year Ended December 31 2020 % Change 2019 % Change 2018 Adjusted Operating Revenue Premium Income Group Life $ 1,640.5  (1.3) % $ 1,662.0  4.9  % $ 1,583.7  Accidental Death & Dismemberment 163.9  (1.1) 165.7  6.0  156.3  Total Premium Income 1,804.4  (1.3) 1,827.7  5.0  1,740.0  Net Investment Income 97.2  (9.5) 107.4  0.8  106.5  Other Income 2.4  (11.1) 2.7  (42.6) 4.7  Total 1,904.0  (1.7) 1,937.8  4.7  1,851.2  Benefits and Expenses Benefits and Change in Reserves for Future Benefits 1,470.4  11.9  1,314.1  6.2  1,237.7  Commissions 143.2  (3.0) 147.7  4.7  141.1  Deferral of Acquisition Costs (36.0) (4.8) (37.8) (1.0) (38.2) Amortization of Deferred Acquisition Costs 39.3  3.1  38.1  6.1  35.9  Other Expenses 205.3  (1.8) 209.0  (2.6) 214.6  Total 1,822.2  9.0  1,671.1  5.0  1,591.1  Adjusted Operating Income $ 81.8  (69.3) $ 266.7  2.5  $ 260.1  Operating Ratios (% of Premium Income): Benefit Ratio 81.5  % 71.9  % 71.1  % Other Expense Ratio 11.4  % 11.4  % 12.3  % Adjusted Operating Income Ratio 4.5  % 14.6  % 14.9  % Persistency: Group Life 88.8  % 90.6  % 91.2  % Accidental Death & Dismemberment 88.2  % 89.9  % 89.9  % 66