RESULTS OF OPERATIONS KWh Sales/Degree Days Summary of KWh Energy Sales (a) Heating degree days are calculated on a 55 degree temperature base. (b) Normal Heating/Cooling represents the thirty-year average of degree days. (c) Cooling degree days are calculated on a 65 degree temperature base. 174 Summary of Heating and Cooling Degree Days Years Ended December 31, 2020 2019 2018 (in degree days) Actual – Heating (a) 3,352  3,782  3,886  Normal – Heating (b) 3,742  3,740  3,747  Actual – Cooling (c) 928  940  1,132  Normal – Cooling (b) 854  849  849  Heating degree days and cooling degree days are metrics commonly used in the utility industry as a measure of the impact of weather on revenues. Years Ended December 31, 2020 2019 2018 (in millions of KWhs) Retail: Residential 5,464  5,409  5,731  Commercial 4,475  4,685  4,851  Industrial 7,225  7,589  7,836  Miscellaneous 67  69  71  Total Retail 17,231  17,752  18,489  Wholesale 7,135  8,268  10,873  Total KWhs 24,366  26,020  29,362 