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 2019 % Change 2018 % Change 2017 Adjusted Operating Revenue Premium Income Group Life $ 1,662.0  4.9  % $ 1,583.7  7.9  % $ 1,467.5  Accidental Death & Dismemberment 165.7  6.0  156.3  6.0  147.5  Total Premium Income 1,827.7  5.0  1,740.0  7.7  1,615.0  Net Investment Income 107.4  0.8  106.5  (3.1) 109.9  Other Income 2.7  (42.6) 4.7  (2.1) 4.8  Total 1,937.8  4.7  1,851.2  7.0  1,729.7  Benefits and Expenses Benefits and Change in Reserves for Future Benefits 1,314.1  6.2  1,237.7  5.8  1,169.8  Commissions 147.7  4.7  141.1  7.5  131.3  Deferral of Acquisition Costs (37.8) (1.0) (38.2) 5.5  (36.2) Amortization of Deferred Acquisition Costs 38.1  6.1  35.9  12.5  31.9  Other Expenses 209.0  (2.6) 214.6  (1.3) 217.4  Total 1,671.1  5.0  1,591.1  5.1  1,514.2  Income Before Income Tax and Net Realized Investment Gains and Losses 266.7  2.5  260.1  20.7  215.5  UDB Reserve Increase —  —  —  N.M.  18.5  Adjusted Operating Income $ 266.7  2.5  $ 260.1  11.2  $ 234.0  Operating Ratios (% of Premium Income): Benefit Ratio 71.9  % 71.1  % 72.4  % Benefit Ratio Excluding UDB Reserve Increase 71.3  % Other Expense Ratio 11.4  % 12.3  % 13.5  % Income Ratio 13.3  % Adjusted Operating Income Ratio 14.6  % 14.9  % 14.5  % Persistency: Group Life 90.6  % 91.2  % 88.0  % Accidental Death & Dismemberment 89.9  % 89.9  % 87.2  % N.M. = not a meaningful percentage 60