ELECTRONIC CONTROL UNIT FOR A HYBRID VEHICLE

An electronic control unit (70) according to the invention is configured to count the number of times of charging opportunities that a hybrid vehicle is in a state where external charging is available in a predetermined period, as the number of times of opportunities, the number of times of the external charging that the vehicle performed in the predetermined period, as the number of times of charging, and to calculate and store a ratio of the number of times of charging to the number of times of opportunities, as a charging frequency.